Home |
Search |
Today's Posts |
|
Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
Reply |
|
|
LinkBack | Thread Tools | Display Modes |
#1
|
|||
|
|||
Vampire Appliances
I was watching the local ABC News and they had a piece on vampire
appliances. They said that an appliance could be using about 5 watts when it's turned off, and that's about $4.00 a month. This sounded a bit high to me. But since I don't get an electric bill, I have no way to tell. 5 watt-hours times 730 hours a month is 3650 watt-hours or 3.65 kWh. More than a dollar a kWh? -- @@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@ h@e@r@e@@ ###Got a Question about ELECTRONICS? Check HERE First:### http://users.pandora.be/educypedia/e...s/databank.htm My email address is whitelisted. *All* email sent to it goes directly to the trash unless you add NOSPAM in the Subject: line with other stuff. alondra101 at hotmail.com Don't be ripped off by the big book dealers. Go to the URL that will give you a choice and save you money(up to half). http://www.everybookstore.com You'll be glad you did! Just when you thought you had all this figured out, the gov't changed it: http://physics.nist.gov/cuu/Units/binary.html @@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@ u@e@n@t@@ |
#2
|
|||
|
|||
Vampire Appliances
In sci.electronics.misc Watson A.Name - "Watt Sun" wrote:
I was watching the local ABC News and they had a piece on vampire appliances. They said that an appliance could be using about 5 watts when it's turned off, and that's about $4.00 a month. This sounded a bit high to me. But since I don't get an electric bill, I have no way to tell. 5 watt-hours times 730 hours a month is 3650 watt-hours or 3.65 kWh. More than a dollar a kWh? Maybe they are talking about all the 5W loads. 20 5W loads does not sound utterly unreasonable. Some devices draw lots more power when "off". My satellite reciever draws almost exactly the same power when off and when on. Off is around 30W, on around 32. -- http://inquisitor.i.am/ | | Ian Stirling. ---------------------------+-------------------------+-------------------------- My inner child can beat up your inner child. - Alex Greenbank |
#3
|
|||
|
|||
Vampire Appliances
In sci.electronics.misc Watson A.Name - "Watt Sun" wrote:
I was watching the local ABC News and they had a piece on vampire appliances. They said that an appliance could be using about 5 watts when it's turned off, and that's about $4.00 a month. This sounded a bit high to me. But since I don't get an electric bill, I have no way to tell. 5 watt-hours times 730 hours a month is 3650 watt-hours or 3.65 kWh. More than a dollar a kWh? Maybe they are talking about all the 5W loads. 20 5W loads does not sound utterly unreasonable. Some devices draw lots more power when "off". My satellite reciever draws almost exactly the same power when off and when on. Off is around 30W, on around 32. -- http://inquisitor.i.am/ | | Ian Stirling. ---------------------------+-------------------------+-------------------------- My inner child can beat up your inner child. - Alex Greenbank |
#4
|
|||
|
|||
Vampire Appliances
"Ian Stirling" wrote ...
Some devices draw lots more power when "off". My satellite reciever draws almost exactly the same power when off and when on. Off is around 30W, on around 32. The way many modern microcontroller-run "appliances" work, they need to maintain their processes between uses (particularly external data-driven things like satellite receivers). Many (most?) of these appliances are designed to have only a "cosmetic" OFF function to satisfy more old-fashioned users who grew up in the era of turning things off to save power. Even VCRs from 15 years ago only blanked the front-panel display in "off" mode. Some of them actually label the mode "Standby" rather than "Off" which is more intelectually honest. |
#5
|
|||
|
|||
Vampire Appliances
"Ian Stirling" wrote ...
Some devices draw lots more power when "off". My satellite reciever draws almost exactly the same power when off and when on. Off is around 30W, on around 32. The way many modern microcontroller-run "appliances" work, they need to maintain their processes between uses (particularly external data-driven things like satellite receivers). Many (most?) of these appliances are designed to have only a "cosmetic" OFF function to satisfy more old-fashioned users who grew up in the era of turning things off to save power. Even VCRs from 15 years ago only blanked the front-panel display in "off" mode. Some of them actually label the mode "Standby" rather than "Off" which is more intelectually honest. |
#6
|
|||
|
|||
Vampire Appliances
The vampire thing was started a few years back by Power Integrations Corp
(afik) to push their high efficiency off-line switching supplies for standby power. http://www.powerint.com/slayingvampirespr.htm http://www.powerint.com/nasdaqopeningpr.htm Corny, Eh? Oppie "Watson A.Name - Watt Sun" wrote in message m... I was watching the local ABC News and they had a piece on vampire appliances. They said that an appliance could be using about 5 watts when it's turned off, and that's about $4.00 a month. This sounded a bit high to me. But since I don't get an electric bill, I have no way to tell. 5 watt-hours times 730 hours a month is 3650 watt-hours or 3.65 kWh. More than a dollar a kWh? |
#7
|
|||
|
|||
Vampire Appliances
The vampire thing was started a few years back by Power Integrations Corp
(afik) to push their high efficiency off-line switching supplies for standby power. http://www.powerint.com/slayingvampirespr.htm http://www.powerint.com/nasdaqopeningpr.htm Corny, Eh? Oppie "Watson A.Name - Watt Sun" wrote in message m... I was watching the local ABC News and they had a piece on vampire appliances. They said that an appliance could be using about 5 watts when it's turned off, and that's about $4.00 a month. This sounded a bit high to me. But since I don't get an electric bill, I have no way to tell. 5 watt-hours times 730 hours a month is 3650 watt-hours or 3.65 kWh. More than a dollar a kWh? |
#8
|
|||
|
|||
Vampire Appliances
All appliances that use a microcontroler for their operation require some
power to be maintained. The off switch on most devices today, only shuts of the display, and some non required circuitry if that. In the case where there are motors, heating elements, and other similar types of apparatus used in the appliances, when in the off mode, these sections are disabled. In the case of TV sets, the scan circuits, audio output stages, and the front end tuner are disabled, because the horizontal and HV outputs sections are disabled. The main processor is still running. Infact on all modern equipment, where there is a remote control, or any type of auto function, the microprocessor and its support circuitry must be running to be able to respond. There are also many devices where the power switch is purely cosmetic, and the device is running all the time as normal. They only switch off the front panel lights, and any displays to make it look like it is off. I have a Scientific Atlanta digital box for my TV set. When it is turned off, the time is showing like a clock. Internally, the unit is still working fully, and the TV will even work on the same channel. It does however not allow the channels to be changed when in the off mode, but the output is operating fully. It is pulling about 30 Watts from the AC all the time. I cannot unplug it from the AC, because I would have to get it re-initialized by the service provider, and that can take about 15 to 20 minutes each time I want to use the TV. Infact, the instruction manual indicates that the unit can be left on all the time. There is no difference. All your modern electric clocks that use an LED display will draw about 5 to 8 Watts on the average. Microwave ovens and TV sets will draw the same amount when in the off mode. If you have an electric stove or any device that has an electric clock and or a remote control to switch the power on and off will also draw this amount. This also includes all models of cordless phones. In the province of Quebec, Canada, electric power costs an average of about $0.04 US or $0.06 Cdn per kW/Hr. The typical home has about 10 devices that draw about 6 Watts AC average when in the off mode. This is about 60 Watts of power being used all the time. This is 0.06 kW each hour. This works to about This works to about $0.06 US per day, or about $0.09 Cdn per day of electricity. This is not very bad, considering the total cost per month of operating a home. The only other solution is to purchase all 1960's or earlier appliances and devices for your home, if you can find them. You will be spending all your time scrounging for parts and continuously fixing them. Infact, the old 1960's electric clocks with motors in them, required more current to operate than today's modern LED and LCD clocks. The earlier appliances when operating required much more wattage to get the same job done, therefore, you will not win with this situation. -- Greetings, Jerry Greenberg GLG Technologies GLG ========================================= WebPage http://www.zoom-one.com Electronics http://www.zoom-one.com/electron.htm Instruments http://www.zoom-one.com/glgtech.htm ========================================= "Watson A.Name - Watt Sun" wrote in message m... I was watching the local ABC News and they had a piece on vampire appliances. They said that an appliance could be using about 5 watts when it's turned off, and that's about $4.00 a month. This sounded a bit high to me. But since I don't get an electric bill, I have no way to tell. 5 watt-hours times 730 hours a month is 3650 watt-hours or 3.65 kWh. More than a dollar a kWh? -- @@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@ h@e@r@e@@ ###Got a Question about ELECTRONICS? Check HERE First:### http://users.pandora.be/educypedia/e...s/databank.htm My email address is whitelisted. *All* email sent to it goes directly to the trash unless you add NOSPAM in the Subject: line with other stuff. alondra101 at hotmail.com Don't be ripped off by the big book dealers. Go to the URL that will give you a choice and save you money(up to half). http://www.everybookstore.com You'll be glad you did! Just when you thought you had all this figured out, the gov't changed it: http://physics.nist.gov/cuu/Units/binary.html @@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@ u@e@n@t@@ |
#9
|
|||
|
|||
Vampire Appliances
All appliances that use a microcontroler for their operation require some
power to be maintained. The off switch on most devices today, only shuts of the display, and some non required circuitry if that. In the case where there are motors, heating elements, and other similar types of apparatus used in the appliances, when in the off mode, these sections are disabled. In the case of TV sets, the scan circuits, audio output stages, and the front end tuner are disabled, because the horizontal and HV outputs sections are disabled. The main processor is still running. Infact on all modern equipment, where there is a remote control, or any type of auto function, the microprocessor and its support circuitry must be running to be able to respond. There are also many devices where the power switch is purely cosmetic, and the device is running all the time as normal. They only switch off the front panel lights, and any displays to make it look like it is off. I have a Scientific Atlanta digital box for my TV set. When it is turned off, the time is showing like a clock. Internally, the unit is still working fully, and the TV will even work on the same channel. It does however not allow the channels to be changed when in the off mode, but the output is operating fully. It is pulling about 30 Watts from the AC all the time. I cannot unplug it from the AC, because I would have to get it re-initialized by the service provider, and that can take about 15 to 20 minutes each time I want to use the TV. Infact, the instruction manual indicates that the unit can be left on all the time. There is no difference. All your modern electric clocks that use an LED display will draw about 5 to 8 Watts on the average. Microwave ovens and TV sets will draw the same amount when in the off mode. If you have an electric stove or any device that has an electric clock and or a remote control to switch the power on and off will also draw this amount. This also includes all models of cordless phones. In the province of Quebec, Canada, electric power costs an average of about $0.04 US or $0.06 Cdn per kW/Hr. The typical home has about 10 devices that draw about 6 Watts AC average when in the off mode. This is about 60 Watts of power being used all the time. This is 0.06 kW each hour. This works to about This works to about $0.06 US per day, or about $0.09 Cdn per day of electricity. This is not very bad, considering the total cost per month of operating a home. The only other solution is to purchase all 1960's or earlier appliances and devices for your home, if you can find them. You will be spending all your time scrounging for parts and continuously fixing them. Infact, the old 1960's electric clocks with motors in them, required more current to operate than today's modern LED and LCD clocks. The earlier appliances when operating required much more wattage to get the same job done, therefore, you will not win with this situation. -- Greetings, Jerry Greenberg GLG Technologies GLG ========================================= WebPage http://www.zoom-one.com Electronics http://www.zoom-one.com/electron.htm Instruments http://www.zoom-one.com/glgtech.htm ========================================= "Watson A.Name - Watt Sun" wrote in message m... I was watching the local ABC News and they had a piece on vampire appliances. They said that an appliance could be using about 5 watts when it's turned off, and that's about $4.00 a month. This sounded a bit high to me. But since I don't get an electric bill, I have no way to tell. 5 watt-hours times 730 hours a month is 3650 watt-hours or 3.65 kWh. More than a dollar a kWh? -- @@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@ h@e@r@e@@ ###Got a Question about ELECTRONICS? Check HERE First:### http://users.pandora.be/educypedia/e...s/databank.htm My email address is whitelisted. *All* email sent to it goes directly to the trash unless you add NOSPAM in the Subject: line with other stuff. alondra101 at hotmail.com Don't be ripped off by the big book dealers. Go to the URL that will give you a choice and save you money(up to half). http://www.everybookstore.com You'll be glad you did! Just when you thought you had all this figured out, the gov't changed it: http://physics.nist.gov/cuu/Units/binary.html @@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@ u@e@n@t@@ |
#10
|
|||
|
|||
Vampire Appliances
Whereas On Mon, 6 Oct 2003 06:58:23 -0700, "Richard Crowley"
scribbled: , I thus relpy: "Ian Stirling" wrote ... Some devices draw lots more power when "off". My satellite reciever draws almost exactly the same power when off and when on. Off is around 30W, on around 32. The way many modern microcontroller-run "appliances" work, they need to maintain their processes between uses (particularly external data-driven things like satellite receivers). Many (most?) of these appliances are designed to have only a "cosmetic" OFF function to satisfy more old-fashioned users who grew up in the era of turning things off to save power. Even VCRs from 15 years ago only blanked the front-panel display in "off" mode. Some of them actually label the mode "Standby" rather than "Off" which is more intelectually honest. Actually, that chip/circuite (the display), stayed on. I'd have to check some of my vintage machines, but you'd thing they'd shut off the syscon, and analong circuits. -- Gary J. Tait . Email is at yahoo.com ; ID:classicsat |
#11
|
|||
|
|||
Vampire Appliances
Whereas On Mon, 6 Oct 2003 06:58:23 -0700, "Richard Crowley"
scribbled: , I thus relpy: "Ian Stirling" wrote ... Some devices draw lots more power when "off". My satellite reciever draws almost exactly the same power when off and when on. Off is around 30W, on around 32. The way many modern microcontroller-run "appliances" work, they need to maintain their processes between uses (particularly external data-driven things like satellite receivers). Many (most?) of these appliances are designed to have only a "cosmetic" OFF function to satisfy more old-fashioned users who grew up in the era of turning things off to save power. Even VCRs from 15 years ago only blanked the front-panel display in "off" mode. Some of them actually label the mode "Standby" rather than "Off" which is more intelectually honest. Actually, that chip/circuite (the display), stayed on. I'd have to check some of my vintage machines, but you'd thing they'd shut off the syscon, and analong circuits. -- Gary J. Tait . Email is at yahoo.com ; ID:classicsat |
#12
|
|||
|
|||
Vampire Appliances
Ian Stirling wrote:
In sci.electronics.misc Watson A.Name - "Watt Sun" wrote: I was watching the local ABC News and they had a piece on vampire appliances. They said that an appliance could be using about 5 watts when it's turned off, and that's about $4.00 a month. This sounded a bit high to me. But since I don't get an electric bill, I have no way to tell. 5 watt-hours times 730 hours a month is 3650 watt-hours or 3.65 kWh. More than a dollar a kWh? Maybe they are talking about all the 5W loads. 20 5W loads does not sound utterly unreasonable. Some devices draw lots more power when "off". My satellite reciever draws almost exactly the same power when off and when on. Off is around 30W, on around 32. It's the third article he (for today, Oct 6, but who knows later..) http://abclocal.go.com/kabc/features/consumer/ They mention that sat rcvrs draw almost as much power. What did you use to measure the power with? A DMM on the AC current range? Then multiply by the line voltage? I sure miss my Amprobe, which got stolen. Really handy, however it required that the hot lead of the line cord be separated from the others. -- ----------------(from OED Mini-Dictionary)----------------- PUNCTUATION - Apostrophe Incorrect uses: (i) the apostrophe must not be used with a plural where there is no possessive sense, as in ~tea's are served here~; (ii) there is no such word as ~her's, our's, their's, your's~. Confusions: it's = it is or it has (not 'belonging to it'); correct uses are ~it's here~ (= it is here); ~it's gone~ (= it has gone); but ~the dog wagged its tail~ (no apostrophe). ----------------(For the Apostrophe challenged)---------------- From a fully deputized officer of the Apostrophe Police! Spammers use Weapons of Mass Distraction! I bought some batteries, but they weren't included, so I had to buy them again. -- Steven Wright FOR SALE: Nice parachute: never opened - used once. (Problem) Evidence of leak on right main landing gear (Solution) Evidence removed F o d d e r f o r s t u p i d " n o t e n o u g h i n c l d u d e d t e x t " e r r o r m s g .. |
#13
|
|||
|
|||
Vampire Appliances
Ian Stirling wrote:
In sci.electronics.misc Watson A.Name - "Watt Sun" wrote: I was watching the local ABC News and they had a piece on vampire appliances. They said that an appliance could be using about 5 watts when it's turned off, and that's about $4.00 a month. This sounded a bit high to me. But since I don't get an electric bill, I have no way to tell. 5 watt-hours times 730 hours a month is 3650 watt-hours or 3.65 kWh. More than a dollar a kWh? Maybe they are talking about all the 5W loads. 20 5W loads does not sound utterly unreasonable. Some devices draw lots more power when "off". My satellite reciever draws almost exactly the same power when off and when on. Off is around 30W, on around 32. It's the third article he (for today, Oct 6, but who knows later..) http://abclocal.go.com/kabc/features/consumer/ They mention that sat rcvrs draw almost as much power. What did you use to measure the power with? A DMM on the AC current range? Then multiply by the line voltage? I sure miss my Amprobe, which got stolen. Really handy, however it required that the hot lead of the line cord be separated from the others. -- ----------------(from OED Mini-Dictionary)----------------- PUNCTUATION - Apostrophe Incorrect uses: (i) the apostrophe must not be used with a plural where there is no possessive sense, as in ~tea's are served here~; (ii) there is no such word as ~her's, our's, their's, your's~. Confusions: it's = it is or it has (not 'belonging to it'); correct uses are ~it's here~ (= it is here); ~it's gone~ (= it has gone); but ~the dog wagged its tail~ (no apostrophe). ----------------(For the Apostrophe challenged)---------------- From a fully deputized officer of the Apostrophe Police! Spammers use Weapons of Mass Distraction! I bought some batteries, but they weren't included, so I had to buy them again. -- Steven Wright FOR SALE: Nice parachute: never opened - used once. (Problem) Evidence of leak on right main landing gear (Solution) Evidence removed F o d d e r f o r s t u p i d " n o t e n o u g h i n c l d u d e d t e x t " e r r o r m s g .. |
#14
|
|||
|
|||
Vampire Appliances
Jerry G. wrote:
[snip] Infact, the old 1960's electric clocks with motors in them, required more current to operate than today's modern LED and LCD clocks. The quartz sweep second hand clocks run for a year off a single AA cell. So no power at all needed from the wall outlet. The earlier appliances when operating required much more wattage to get the same job done, therefore, you will not win with this situation. One of the ladies at work replaced her old fridge with a new energy efficient one. Her electric bill went down fifty dollars a month(!) -- ----------------(from OED Mini-Dictionary)----------------- PUNCTUATION - Apostrophe Incorrect uses: (i) the apostrophe must not be used with a plural where there is no possessive sense, as in ~tea's are served here~; (ii) there is no such word as ~her's, our's, their's, your's~. Confusions: it's = it is or it has (not 'belonging to it'); correct uses are ~it's here~ (= it is here); ~it's gone~ (= it has gone); but ~the dog wagged its tail~ (no apostrophe). ----------------(For the Apostrophe challenged)---------------- From a fully deputized officer of the Apostrophe Police! Spammers use Weapons of Mass Distraction! I bought some batteries, but they weren't included, so I had to buy them again. -- Steven Wright FOR SALE: Nice parachute: never opened - used once. (Problem) Evidence of leak on right main landing gear (Solution) Evidence removed F o d d e r f o r s t u p i d " n o t e n o u g h i n c l d u d e d t e x t " e r r o r m s g .. |
#15
|
|||
|
|||
Vampire Appliances
Jerry G. wrote:
[snip] Infact, the old 1960's electric clocks with motors in them, required more current to operate than today's modern LED and LCD clocks. The quartz sweep second hand clocks run for a year off a single AA cell. So no power at all needed from the wall outlet. The earlier appliances when operating required much more wattage to get the same job done, therefore, you will not win with this situation. One of the ladies at work replaced her old fridge with a new energy efficient one. Her electric bill went down fifty dollars a month(!) -- ----------------(from OED Mini-Dictionary)----------------- PUNCTUATION - Apostrophe Incorrect uses: (i) the apostrophe must not be used with a plural where there is no possessive sense, as in ~tea's are served here~; (ii) there is no such word as ~her's, our's, their's, your's~. Confusions: it's = it is or it has (not 'belonging to it'); correct uses are ~it's here~ (= it is here); ~it's gone~ (= it has gone); but ~the dog wagged its tail~ (no apostrophe). ----------------(For the Apostrophe challenged)---------------- From a fully deputized officer of the Apostrophe Police! Spammers use Weapons of Mass Distraction! I bought some batteries, but they weren't included, so I had to buy them again. -- Steven Wright FOR SALE: Nice parachute: never opened - used once. (Problem) Evidence of leak on right main landing gear (Solution) Evidence removed F o d d e r f o r s t u p i d " n o t e n o u g h i n c l d u d e d t e x t " e r r o r m s g .. |
#16
|
|||
|
|||
Vampire Appliances
On Mon, 06 Oct 2003 13:02:09 -0700, Lizard Blizzard
wrote: Jerry G. wrote: [snip] Infact, the old 1960's electric clocks with motors in them, required more current to operate than today's modern LED and LCD clocks. The quartz sweep second hand clocks run for a year off a single AA cell. So no power at all needed from the wall outlet. The earlier appliances when operating required much more wattage to get the same job done, therefore, you will not win with this situation. One of the ladies at work replaced her old fridge with a new energy efficient one. Her electric bill went down fifty dollars a month(!) Old refrigerators and freezers wasted most of their energy in generating heat, which if in a confined room, would lower the efficiency of the unit itself, yet alone run the ambient temp of the room up to an un livable level, requiring the need for an air conditioner of some sort. I have a full blown media room .. full stereo system (where the main amp/pre amp is ON but display is off all the time .. phono pre amp for my Linear .. Dolby 5.1 amp set up (on all the time) 32'HDTV .. screen is the only thing that turns off, so it generates heat .. two computers (P iv's) that generate a gang of heat (did go to an LCD display which cut down on the heat from a monitor. .. but all along the back wall behind a vented folding door set is a pantry, which includes a huge side by side ref/freezer. so I have to have an 8000 btu air conditioner running 9 months out of the year. plus a Honeywell Air cleaner to keep from having to open and CLEAN everything every month! |
#17
|
|||
|
|||
Vampire Appliances
On Mon, 06 Oct 2003 13:02:09 -0700, Lizard Blizzard
wrote: Jerry G. wrote: [snip] Infact, the old 1960's electric clocks with motors in them, required more current to operate than today's modern LED and LCD clocks. The quartz sweep second hand clocks run for a year off a single AA cell. So no power at all needed from the wall outlet. The earlier appliances when operating required much more wattage to get the same job done, therefore, you will not win with this situation. One of the ladies at work replaced her old fridge with a new energy efficient one. Her electric bill went down fifty dollars a month(!) Old refrigerators and freezers wasted most of their energy in generating heat, which if in a confined room, would lower the efficiency of the unit itself, yet alone run the ambient temp of the room up to an un livable level, requiring the need for an air conditioner of some sort. I have a full blown media room .. full stereo system (where the main amp/pre amp is ON but display is off all the time .. phono pre amp for my Linear .. Dolby 5.1 amp set up (on all the time) 32'HDTV .. screen is the only thing that turns off, so it generates heat .. two computers (P iv's) that generate a gang of heat (did go to an LCD display which cut down on the heat from a monitor. .. but all along the back wall behind a vented folding door set is a pantry, which includes a huge side by side ref/freezer. so I have to have an 8000 btu air conditioner running 9 months out of the year. plus a Honeywell Air cleaner to keep from having to open and CLEAN everything every month! |
#18
|
|||
|
|||
Current Sense Transformer
I have a manutech current sense transformer I picked up from a junk box buy,
and I've been trying to build a simple kill-a-watt meter. Here is my schematic: 3 to 2000 | | | | -----+---------------- +----| | | | | ^ | C|| | C| .-. | AC C|| | C| | | 100 ohms V Sense | C|| | C| | | | +----| | | | '-' | | | | | v | | ------+---------------- created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de Now, this seems to approximately work for the three devices I've tried it on: 100W light bulb, Vsense = 0.120V, computed power = 94W 25W light bulb, Vsense = 0.028V, computed power = 22W AC Motor , Vsense = 0.220V, computed power = 167W However, the question arises whether this will work for appliances. 1) I have a simple A/C meter. Does that do a passable job in this circumstance? 2) What about power factor? Since I'm residential, I know I'm paying for 'real power'. Does this setup measure what I'm paying for? 3) This is a pretty small transformer. I have no specs for it. It seems like the power through the thing is miniscule. However, I'm slightly worried about subjecting my refrigerator to this device. Any thoughts on that? 4) I could do some fancy software on a PIC to try and integrate the waveform in order to get a better approximation of real power in the cases where the waveform has been mashed by appliances. Is it worth it? Will the shape of the waveform be preserved through the transformer? Do you know the percentage difference between this and just using power = Vpeak^2 / 2R? (which is what I'm guessing my A/C meter does.) with thanks, Bob Monsen |
#19
|
|||
|
|||
Current Sense Transformer
I have a manutech current sense transformer I picked up from a junk box buy,
and I've been trying to build a simple kill-a-watt meter. Here is my schematic: 3 to 2000 | | | | -----+---------------- +----| | | | | ^ | C|| | C| .-. | AC C|| | C| | | 100 ohms V Sense | C|| | C| | | | +----| | | | '-' | | | | | v | | ------+---------------- created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de Now, this seems to approximately work for the three devices I've tried it on: 100W light bulb, Vsense = 0.120V, computed power = 94W 25W light bulb, Vsense = 0.028V, computed power = 22W AC Motor , Vsense = 0.220V, computed power = 167W However, the question arises whether this will work for appliances. 1) I have a simple A/C meter. Does that do a passable job in this circumstance? 2) What about power factor? Since I'm residential, I know I'm paying for 'real power'. Does this setup measure what I'm paying for? 3) This is a pretty small transformer. I have no specs for it. It seems like the power through the thing is miniscule. However, I'm slightly worried about subjecting my refrigerator to this device. Any thoughts on that? 4) I could do some fancy software on a PIC to try and integrate the waveform in order to get a better approximation of real power in the cases where the waveform has been mashed by appliances. Is it worth it? Will the shape of the waveform be preserved through the transformer? Do you know the percentage difference between this and just using power = Vpeak^2 / 2R? (which is what I'm guessing my A/C meter does.) with thanks, Bob Monsen |
#20
|
|||
|
|||
Vampire Appliances
On Mon, 6 Oct 2003 06:21:42 -0700, Watson A.Name - "Watt Sun"
wrote: I was watching the local ABC News and they had a piece on vampire appliances. They said that an appliance could be using about 5 watts when it's turned off, and that's about $4.00 a month. This sounded a bit high to me. But since I don't get an electric bill, I have no way to tell. 5 watt-hours times 730 hours a month is 3650 watt-hours or 3.65 kWh. More than a dollar a kWh? This is probably good info. if they mean average wasted power around the house as a result of power supplies idling without doing any work. I opened up my typewriter some years ago and was surprised at how hot it was inside. I got my clamp on ammeter and went around the house measuring everything. Here's some of what I found (calculated on 120 VAC): CD player OFF 10 watts Cable amplifier ON:noreading Cable convertor OFF 16.3 watts GE TV OFF: no reading Microwave OFF: 4.3 watts Sony TV OFF: 12 watts VCR OFF 14 watts Computer printer OFF 9.6 watts Word Processing TypeW 10.0 watts Police Scanner OFF 3.0 watts Computer scanner OFF 5 Watts It amounts to ~$5+ a month for the stuff that doesn't provide any useful function when off. I think that is significant. Worth installing a switch for things one uses infrequently. Wonder how much power that amounts to nationwide? -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
#21
|
|||
|
|||
Vampire Appliances
On Mon, 6 Oct 2003 06:21:42 -0700, Watson A.Name - "Watt Sun"
wrote: I was watching the local ABC News and they had a piece on vampire appliances. They said that an appliance could be using about 5 watts when it's turned off, and that's about $4.00 a month. This sounded a bit high to me. But since I don't get an electric bill, I have no way to tell. 5 watt-hours times 730 hours a month is 3650 watt-hours or 3.65 kWh. More than a dollar a kWh? This is probably good info. if they mean average wasted power around the house as a result of power supplies idling without doing any work. I opened up my typewriter some years ago and was surprised at how hot it was inside. I got my clamp on ammeter and went around the house measuring everything. Here's some of what I found (calculated on 120 VAC): CD player OFF 10 watts Cable amplifier ON:noreading Cable convertor OFF 16.3 watts GE TV OFF: no reading Microwave OFF: 4.3 watts Sony TV OFF: 12 watts VCR OFF 14 watts Computer printer OFF 9.6 watts Word Processing TypeW 10.0 watts Police Scanner OFF 3.0 watts Computer scanner OFF 5 Watts It amounts to ~$5+ a month for the stuff that doesn't provide any useful function when off. I think that is significant. Worth installing a switch for things one uses infrequently. Wonder how much power that amounts to nationwide? -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
#22
|
|||
|
|||
Vampire Appliances
oldsoundguy wrote:
[snip] my Linear .. Dolby 5.1 amp set up (on all the time) 32'HDTV .. screen WOW! You must have a theater with a screen that big! [snip] -- ----------------(from OED Mini-Dictionary)----------------- PUNCTUATION - Apostrophe Incorrect uses: (i) the apostrophe must not be used with a plural where there is no possessive sense, as in ~tea's are served here~; (ii) there is no such word as ~her's, our's, their's, your's~. Confusions: it's = it is or it has (not 'belonging to it'); correct uses are ~it's here~ (= it is here); ~it's gone~ (= it has gone); but ~the dog wagged its tail~ (no apostrophe). ----------------(For the Apostrophe challenged)---------------- From a fully deputized officer of the Apostrophe Police! Spammers use Weapons of Mass Distraction! I bought some batteries, but they weren't included, so I had to buy them again. -- Steven Wright FOR SALE: Nice parachute: never opened - used once. (Problem) Evidence of leak on right main landing gear (Solution) Evidence removed F o d d e r f o r s t u p i d " n o t e n o u g h i n c l d u d e d t e x t " e r r o r m s g .. |
#23
|
|||
|
|||
Vampire Appliances
oldsoundguy wrote:
[snip] my Linear .. Dolby 5.1 amp set up (on all the time) 32'HDTV .. screen WOW! You must have a theater with a screen that big! [snip] -- ----------------(from OED Mini-Dictionary)----------------- PUNCTUATION - Apostrophe Incorrect uses: (i) the apostrophe must not be used with a plural where there is no possessive sense, as in ~tea's are served here~; (ii) there is no such word as ~her's, our's, their's, your's~. Confusions: it's = it is or it has (not 'belonging to it'); correct uses are ~it's here~ (= it is here); ~it's gone~ (= it has gone); but ~the dog wagged its tail~ (no apostrophe). ----------------(For the Apostrophe challenged)---------------- From a fully deputized officer of the Apostrophe Police! Spammers use Weapons of Mass Distraction! I bought some batteries, but they weren't included, so I had to buy them again. -- Steven Wright FOR SALE: Nice parachute: never opened - used once. (Problem) Evidence of leak on right main landing gear (Solution) Evidence removed F o d d e r f o r s t u p i d " n o t e n o u g h i n c l d u d e d t e x t " e r r o r m s g .. |
#24
|
|||
|
|||
Current Sense Transformer
"Robert Monsen" wrote in message
newsEkgb.508681$Oz4.358896@rwcrnsc54... I have a manutech current sense transformer I picked up from a junk box buy, and I've been trying to build a simple kill-a-watt meter. Here is my schematic: 3 to 2000 | | | | -----+---------------- +----| | | | | ^ | C|| | C| .-. | AC C|| | C| | | 100 ohms V Sense | C|| | C| | | | +----| | | | '-' | | | | | v | | ------+---------------- created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de Now, this seems to approximately work for the three devices I've tried it on: 100W light bulb, Vsense = 0.120V, computed power = 94W 25W light bulb, Vsense = 0.028V, computed power = 22W AC Motor , Vsense = 0.220V, computed power = 167W However, the question arises whether this will work for appliances. 1) I have a simple A/C meter. Does that do a passable job in this circumstance? 2) What about power factor? Since I'm residential, I know I'm paying for 'real power'. Does this setup measure what I'm paying for? 3) This is a pretty small transformer. I have no specs for it. It seems like the power through the thing is miniscule. However, I'm slightly worried about subjecting my refrigerator to this device. Any thoughts on that? 4) I could do some fancy software on a PIC to try and integrate the waveform in order to get a better approximation of real power in the cases where the waveform has been mashed by appliances. Is it worth it? Will the shape of the waveform be preserved through the transformer? Do you know the percentage difference between this and just using power = Vpeak^2 / 2R? (which is what I'm guessing my A/C meter does.) with thanks, Bob Monsen Bob, What you have there is just a current sensor.. only the beginnings of a wattmeter. You need a bit more circuitry to get a wattmeter. Consider that Watts = Volts * Amps. You only have amps (actually, a scaled representation of amps) from your circuit. What does that leave? Volts and the multiplication function. There are ICs that specifically provide a multiplication function; the MC1495 from ON Semiconductor is the first that comes to mind. There have been several application notes written specifically to show simple wattmeter designs around this chip. Download the spec sheet at http://www.onsemi.com/pub/Collateral/MC1495-D.PDF. A quick web search revealed a simple but versatile design for a wattmeter at http://www.maxim-ic.com/appnotes.cfm...ber/1160/ln/en. You could use that as a starting point for your wattmeter. You would have to add higher voltage and current ranges to get the power levels that you're interested in, and of course, if you want to use your current sensor, you would want to substitute it in place of the sense resistor in the diagram. Answering you questions,; (1) A simple voltmeter on the output of your circuit will only give you a representation of the curremt being drawn by the load. (2) No.. Again, you're only measuring current. (3) Google the web for current transformer design and you'll get a better understanding of how they work, and how to calculate the current/voltage relationship. (4) Forget about using your AC meter for this if you really want to build a wattmeter. Again, the spec sheet for the MC1495 and |
#25
|
|||
|
|||
Current Sense Transformer
"Robert Monsen" wrote in message
newsEkgb.508681$Oz4.358896@rwcrnsc54... I have a manutech current sense transformer I picked up from a junk box buy, and I've been trying to build a simple kill-a-watt meter. Here is my schematic: 3 to 2000 | | | | -----+---------------- +----| | | | | ^ | C|| | C| .-. | AC C|| | C| | | 100 ohms V Sense | C|| | C| | | | +----| | | | '-' | | | | | v | | ------+---------------- created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de Now, this seems to approximately work for the three devices I've tried it on: 100W light bulb, Vsense = 0.120V, computed power = 94W 25W light bulb, Vsense = 0.028V, computed power = 22W AC Motor , Vsense = 0.220V, computed power = 167W However, the question arises whether this will work for appliances. 1) I have a simple A/C meter. Does that do a passable job in this circumstance? 2) What about power factor? Since I'm residential, I know I'm paying for 'real power'. Does this setup measure what I'm paying for? 3) This is a pretty small transformer. I have no specs for it. It seems like the power through the thing is miniscule. However, I'm slightly worried about subjecting my refrigerator to this device. Any thoughts on that? 4) I could do some fancy software on a PIC to try and integrate the waveform in order to get a better approximation of real power in the cases where the waveform has been mashed by appliances. Is it worth it? Will the shape of the waveform be preserved through the transformer? Do you know the percentage difference between this and just using power = Vpeak^2 / 2R? (which is what I'm guessing my A/C meter does.) with thanks, Bob Monsen Bob, What you have there is just a current sensor.. only the beginnings of a wattmeter. You need a bit more circuitry to get a wattmeter. Consider that Watts = Volts * Amps. You only have amps (actually, a scaled representation of amps) from your circuit. What does that leave? Volts and the multiplication function. There are ICs that specifically provide a multiplication function; the MC1495 from ON Semiconductor is the first that comes to mind. There have been several application notes written specifically to show simple wattmeter designs around this chip. Download the spec sheet at http://www.onsemi.com/pub/Collateral/MC1495-D.PDF. A quick web search revealed a simple but versatile design for a wattmeter at http://www.maxim-ic.com/appnotes.cfm...ber/1160/ln/en. You could use that as a starting point for your wattmeter. You would have to add higher voltage and current ranges to get the power levels that you're interested in, and of course, if you want to use your current sensor, you would want to substitute it in place of the sense resistor in the diagram. Answering you questions,; (1) A simple voltmeter on the output of your circuit will only give you a representation of the curremt being drawn by the load. (2) No.. Again, you're only measuring current. (3) Google the web for current transformer design and you'll get a better understanding of how they work, and how to calculate the current/voltage relationship. (4) Forget about using your AC meter for this if you really want to build a wattmeter. Again, the spec sheet for the MC1495 and |
#26
|
|||
|
|||
Current Sense Transformer
What you've got is a current sense transformer. Since the transformer is
small, the best low frequency response is had by using as low a secondary terminating impedance as possible. If you don't know what gauge the primary wire is, it's hard to figure the maximum current that it can take. I usually go by limiting to a 50C temperature rise. You can calculate only Volt-Amps if you measure the voltage and then multiply by your measured current. If you want to measure watts, you would need to multiply (2 or 4 quadrant) in real time the current and voltage to take into account the phase angle (power factor). FWIW take a peek at http://www.elecdesign.com/Articles/I...ArticleID=2191 there are some additionsl links at the bottom of that page. Oppie -- For correct response address, remove -nospam- ========= "Robert Monsen" wrote in message newsEkgb.508681$Oz4.358896@rwcrnsc54... I have a manutech current sense transformer I picked up from a junk box buy, and I've been trying to build a simple kill-a-watt meter. Here is my schematic: 3 to 2000 | | | | -----+---------------- +----| | | | | ^ | C|| | C| .-. | AC C|| | C| | | 100 ohms V Sense | C|| | C| | | | +----| | | | '-' | | | | | v | | ------+---------------- created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de Now, this seems to approximately work for the three devices I've tried it on: 100W light bulb, Vsense = 0.120V, computed power = 94W 25W light bulb, Vsense = 0.028V, computed power = 22W AC Motor , Vsense = 0.220V, computed power = 167W However, the question arises whether this will work for appliances. 1) I have a simple A/C meter. Does that do a passable job in this circumstance? 2) What about power factor? Since I'm residential, I know I'm paying for 'real power'. Does this setup measure what I'm paying for? 3) This is a pretty small transformer. I have no specs for it. It seems like the power through the thing is miniscule. However, I'm slightly worried about subjecting my refrigerator to this device. Any thoughts on that? 4) I could do some fancy software on a PIC to try and integrate the waveform in order to get a better approximation of real power in the cases where the waveform has been mashed by appliances. Is it worth it? Will the shape of the waveform be preserved through the transformer? Do you know the percentage difference between this and just using power = Vpeak^2 / 2R? (which is what I'm guessing my A/C meter does.) with thanks, Bob Monsen |
#27
|
|||
|
|||
Current Sense Transformer
What you've got is a current sense transformer. Since the transformer is
small, the best low frequency response is had by using as low a secondary terminating impedance as possible. If you don't know what gauge the primary wire is, it's hard to figure the maximum current that it can take. I usually go by limiting to a 50C temperature rise. You can calculate only Volt-Amps if you measure the voltage and then multiply by your measured current. If you want to measure watts, you would need to multiply (2 or 4 quadrant) in real time the current and voltage to take into account the phase angle (power factor). FWIW take a peek at http://www.elecdesign.com/Articles/I...ArticleID=2191 there are some additionsl links at the bottom of that page. Oppie -- For correct response address, remove -nospam- ========= "Robert Monsen" wrote in message newsEkgb.508681$Oz4.358896@rwcrnsc54... I have a manutech current sense transformer I picked up from a junk box buy, and I've been trying to build a simple kill-a-watt meter. Here is my schematic: 3 to 2000 | | | | -----+---------------- +----| | | | | ^ | C|| | C| .-. | AC C|| | C| | | 100 ohms V Sense | C|| | C| | | | +----| | | | '-' | | | | | v | | ------+---------------- created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de Now, this seems to approximately work for the three devices I've tried it on: 100W light bulb, Vsense = 0.120V, computed power = 94W 25W light bulb, Vsense = 0.028V, computed power = 22W AC Motor , Vsense = 0.220V, computed power = 167W However, the question arises whether this will work for appliances. 1) I have a simple A/C meter. Does that do a passable job in this circumstance? 2) What about power factor? Since I'm residential, I know I'm paying for 'real power'. Does this setup measure what I'm paying for? 3) This is a pretty small transformer. I have no specs for it. It seems like the power through the thing is miniscule. However, I'm slightly worried about subjecting my refrigerator to this device. Any thoughts on that? 4) I could do some fancy software on a PIC to try and integrate the waveform in order to get a better approximation of real power in the cases where the waveform has been mashed by appliances. Is it worth it? Will the shape of the waveform be preserved through the transformer? Do you know the percentage difference between this and just using power = Vpeak^2 / 2R? (which is what I'm guessing my A/C meter does.) with thanks, Bob Monsen |
#28
|
|||
|
|||
Vampire Appliances
On Mon, 06 Oct 2003 15:51:06 -0700, Lizard Blizzard
wrote: oldsoundguy wrote: [snip] my Linear .. Dolby 5.1 amp set up (on all the time) 32'HDTV .. screen WOW! You must have a theater with a screen that big! [snip] that was the intent!! |
#29
|
|||
|
|||
Vampire Appliances
On Mon, 06 Oct 2003 15:51:06 -0700, Lizard Blizzard
wrote: oldsoundguy wrote: [snip] my Linear .. Dolby 5.1 amp set up (on all the time) 32'HDTV .. screen WOW! You must have a theater with a screen that big! [snip] that was the intent!! |
#30
|
|||
|
|||
Current Sense Transformer
"Tweetldee" wrote in message ... "Robert Monsen" wrote in message newsEkgb.508681$Oz4.358896@rwcrnsc54... I have a manutech current sense transformer I picked up from a junk box buy, and I've been trying to build a simple kill-a-watt meter. Here is my schematic: 3 to 2000 | | | | -----+---------------- +----| | | | | ^ | C|| | C| .-. | AC C|| | C| | | 100 ohms V Sense | C|| | C| | | | +----| | | | '-' | | | | | v | | ------+---------------- created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de Now, this seems to approximately work for the three devices I've tried it on: 100W light bulb, Vsense = 0.120V, computed power = 94W 25W light bulb, Vsense = 0.028V, computed power = 22W AC Motor , Vsense = 0.220V, computed power = 167W However, the question arises whether this will work for appliances. 1) I have a simple A/C meter. Does that do a passable job in this circumstance? 2) What about power factor? Since I'm residential, I know I'm paying for 'real power'. Does this setup measure what I'm paying for? 3) This is a pretty small transformer. I have no specs for it. It seems like the power through the thing is miniscule. However, I'm slightly worried about subjecting my refrigerator to this device. Any thoughts on that? 4) I could do some fancy software on a PIC to try and integrate the waveform in order to get a better approximation of real power in the cases where the waveform has been mashed by appliances. Is it worth it? Will the shape of the waveform be preserved through the transformer? Do you know the percentage difference between this and just using power = Vpeak^2 / 2R? (which is what I'm guessing my A/C meter does.) with thanks, Bob Monsen Bob, What you have there is just a current sensor.. only the beginnings of a wattmeter. You need a bit more circuitry to get a wattmeter. Consider that Watts = Volts * Amps. You only have amps (actually, a scaled representation of amps) from your circuit. Thanks for the help. I guess I was assuming the voltage was line voltage, ie, around 115V. That makes it possible to determine power using only a current sensor. An essential part of the posted 'wattmeter' was my calculator... However, you are right that a better way to determine the voltage across the device makes sense. Another voltage sensor would be one way, say a small power transformer. Using that, I can determine the voltage across the line directly, and use these to generate the display. Regards, Bob Monsen |
#31
|
|||
|
|||
Current Sense Transformer
"Tweetldee" wrote in message ... "Robert Monsen" wrote in message newsEkgb.508681$Oz4.358896@rwcrnsc54... I have a manutech current sense transformer I picked up from a junk box buy, and I've been trying to build a simple kill-a-watt meter. Here is my schematic: 3 to 2000 | | | | -----+---------------- +----| | | | | ^ | C|| | C| .-. | AC C|| | C| | | 100 ohms V Sense | C|| | C| | | | +----| | | | '-' | | | | | v | | ------+---------------- created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de Now, this seems to approximately work for the three devices I've tried it on: 100W light bulb, Vsense = 0.120V, computed power = 94W 25W light bulb, Vsense = 0.028V, computed power = 22W AC Motor , Vsense = 0.220V, computed power = 167W However, the question arises whether this will work for appliances. 1) I have a simple A/C meter. Does that do a passable job in this circumstance? 2) What about power factor? Since I'm residential, I know I'm paying for 'real power'. Does this setup measure what I'm paying for? 3) This is a pretty small transformer. I have no specs for it. It seems like the power through the thing is miniscule. However, I'm slightly worried about subjecting my refrigerator to this device. Any thoughts on that? 4) I could do some fancy software on a PIC to try and integrate the waveform in order to get a better approximation of real power in the cases where the waveform has been mashed by appliances. Is it worth it? Will the shape of the waveform be preserved through the transformer? Do you know the percentage difference between this and just using power = Vpeak^2 / 2R? (which is what I'm guessing my A/C meter does.) with thanks, Bob Monsen Bob, What you have there is just a current sensor.. only the beginnings of a wattmeter. You need a bit more circuitry to get a wattmeter. Consider that Watts = Volts * Amps. You only have amps (actually, a scaled representation of amps) from your circuit. Thanks for the help. I guess I was assuming the voltage was line voltage, ie, around 115V. That makes it possible to determine power using only a current sensor. An essential part of the posted 'wattmeter' was my calculator... However, you are right that a better way to determine the voltage across the device makes sense. Another voltage sensor would be one way, say a small power transformer. Using that, I can determine the voltage across the line directly, and use these to generate the display. Regards, Bob Monsen |
#32
|
|||
|
|||
Current Sense Transformer
In s.com (Oppie):
What you've got is a current sense transformer. Since the transformer is small, the best low frequency response is had by using as low a secondary terminating impedance as possible. If you don't know what gauge the primary wire is, it's hard to figure the maximum current that it can take. I usually go by limiting to a 50C temperature rise. You can calculate only Volt-Amps if you measure the voltage and then multiply by your measured current. If you want to measure watts, you would need to multiply (2 or 4 quadrant) in real time the current and voltage to take into account the phase angle (power factor). FWIW take a peek at http://www.elecdesign.com/Articles/I...ArticleID=2191 there are some additionsl links at the bottom of that page. Oppie Also very prevalent is this writeup on transformers: http://www.ibiblio.org/obp/electricC...s/AC/AC_9.html. Go down past the middle of the page, there is much useful information there. I have a manutech current sense transformer I picked up from a junk box buy, and I've been trying to build a simple kill-a-watt meter. Here is my schematic: 3 to 2000 | | | | -----+---------------- +----| | | | | ^ | C|| | C| .-. | AC C|| | C| | | 100 ohms V Sense | C|| | C| | | | +----| | | | '-' | | | | | v | | ------+---------------- created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de Now, this seems to approximately work for the three devices I've tried it on: 100W light bulb, Vsense = 0.120V, computed power = 94W 25W light bulb, Vsense = 0.028V, computed power = 22W AC Motor , Vsense = 0.220V, computed power = 167W However, the question arises whether this will work for appliances. 1) I have a simple A/C meter. Does that do a passable job in this circumstance? 2) What about power factor? Since I'm residential, I know I'm paying for 'real power'. Does this setup measure what I'm paying for? 3) This is a pretty small transformer. I have no specs for it. It seems like the power through the thing is miniscule. However, I'm slightly worried about subjecting my refrigerator to this device. Any thoughts on that? 4) I could do some fancy software on a PIC to try and integrate the waveform in order to get a better approximation of real power in the cases where the waveform has been mashed by appliances. Is it worth it? Will the shape of the waveform be preserved through the transformer? Do you know the percentage difference between this and just using power = Vpeak^2 / 2R? (which is what I'm guessing my A/C meter does.) with thanks, Bob Monsen |
#33
|
|||
|
|||
Current Sense Transformer
In s.com (Oppie):
What you've got is a current sense transformer. Since the transformer is small, the best low frequency response is had by using as low a secondary terminating impedance as possible. If you don't know what gauge the primary wire is, it's hard to figure the maximum current that it can take. I usually go by limiting to a 50C temperature rise. You can calculate only Volt-Amps if you measure the voltage and then multiply by your measured current. If you want to measure watts, you would need to multiply (2 or 4 quadrant) in real time the current and voltage to take into account the phase angle (power factor). FWIW take a peek at http://www.elecdesign.com/Articles/I...ArticleID=2191 there are some additionsl links at the bottom of that page. Oppie Also very prevalent is this writeup on transformers: http://www.ibiblio.org/obp/electricC...s/AC/AC_9.html. Go down past the middle of the page, there is much useful information there. I have a manutech current sense transformer I picked up from a junk box buy, and I've been trying to build a simple kill-a-watt meter. Here is my schematic: 3 to 2000 | | | | -----+---------------- +----| | | | | ^ | C|| | C| .-. | AC C|| | C| | | 100 ohms V Sense | C|| | C| | | | +----| | | | '-' | | | | | v | | ------+---------------- created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de Now, this seems to approximately work for the three devices I've tried it on: 100W light bulb, Vsense = 0.120V, computed power = 94W 25W light bulb, Vsense = 0.028V, computed power = 22W AC Motor , Vsense = 0.220V, computed power = 167W However, the question arises whether this will work for appliances. 1) I have a simple A/C meter. Does that do a passable job in this circumstance? 2) What about power factor? Since I'm residential, I know I'm paying for 'real power'. Does this setup measure what I'm paying for? 3) This is a pretty small transformer. I have no specs for it. It seems like the power through the thing is miniscule. However, I'm slightly worried about subjecting my refrigerator to this device. Any thoughts on that? 4) I could do some fancy software on a PIC to try and integrate the waveform in order to get a better approximation of real power in the cases where the waveform has been mashed by appliances. Is it worth it? Will the shape of the waveform be preserved through the transformer? Do you know the percentage difference between this and just using power = Vpeak^2 / 2R? (which is what I'm guessing my A/C meter does.) with thanks, Bob Monsen |
#35
|
|||
|
|||
Vampire Appliances
In article ,
says... we can do better. run the important stuff in sleep mode and keep it alive with a super-cap. IR RCVR? eh, might draw a bit too much. All appliances that use a microcontroler for their operation require some power to be maintained. The off switch on most devices today, only shuts of the display, and some non required circuitry if that. In the case where there are motors, heating elements, and other similar types of apparatus used in the appliances, when in the off mode, these sections are disabled. In the case of TV sets, the scan circuits, audio output stages, and the front end tuner are disabled, because the horizontal and HV outputs sections are disabled. The main processor is still running. Infact on all modern equipment, where there is a remote control, or any type of auto function, the microprocessor and its support circuitry must be running to be able to respond. There are also many devices where the power switch is purely cosmetic, and the device is running all the time as normal. They only switch off the front panel lights, and any displays to make it look like it is off. yeah, and when that VCR acts stupid, sometime a power-cycle (un-plug it) is all it takes to get it going again. I have a Scientific Atlanta digital box for my TV set. When it is turned off, the time is showing like a clock. Internally, the unit is still working fully, and the TV will even work on the same channel. It does however not allow the channels to be changed when in the off mode, but the output is operating fully. It is pulling about 30 Watts from the AC all the time. I cannot unplug it from the AC, because I would have to get it re-initialized by the service provider, and that can take about 15 to 20 minutes each time I want to use the TV. then SA must be screwed because Jerrolds/General Instruments and Panasonic boxes can be unplugged for up to 24hrs without needing to be re-hit. call warner cable in houston and ask if they don't send boxes out pre-hit. same for the GI boxes in Balto city except they're not pre- hit, but you can take them when you move and if you don't screw around unpacking, it'll not need to be re-hit. hee, hee... i had an instant (24 hr) install contract through a sales company in a CATV system once and this customer gave me an SA box she found when she moved in. hmm... this system uses Panasonic. not warner - another MSO. after connecting her outside, i checked the channels and the guide channel wasn't where it should be. i've seen 2 systems on the same pole or in diff UG peds before, but this wasn't the case. i was on the border and the MSO's plant info must have been wrong. oh well, it occurred to me later what was wrong and i let 'em know. (doubt anyone cared cause i wasn't sent back.) can you imagine the confusion, finger pointing, and bitching that may have happened if that customer were to be cut off as an illegal hook up when she'd been faithfully paying the bill for months or even years before the tap audit? "i'm sorry maam, i don't show anything indicating a turn-off order. are you sure your TV is connected to the box?" Infact, the instruction manual indicates that the unit can be left on all the time. There is no difference. All your modern electric clocks that use an LED display will draw about 5 to 8 Watts on the average. must be those blasted XFMRs. good case for off-line switchers? Microwave ovens and TV sets will draw the same amount when in the off mode. If you have an electric stove or any device that has an electric clock and or a remote control to switch the power on and off will also draw this amount. This also includes all models of cordless phones. but the wal-wart helps keep the place warm ! :-) think of the savings in heating fuel. [if you ask me,] heat pumps rule. - words added for poetic/musical purposes - why rhyme if it isn't properly syncopated, right? In the province of Quebec, Canada, electric power costs an average of about $0.04 US or $0.06 Cdn per kW/Hr. The typical home has about 10 devices that draw about 6 Watts AC average when in the off mode. This is about 60 Watts of power being used all the time. This is 0.06 kW each hour. This works to about This works to about $0.06 US per day, or about $0.09 Cdn per day of electricity. This is not very bad, considering the total cost per month of operating a home. and leaving that computer on with the monitor off (unless you need the heat) reduces the thermal cycling on the big-chip. The only other solution is to purchase all 1960's or earlier appliances and devices for your home, if you can find them. You will be spending all your time scrounging for parts and continuously fixing them. Infact, the old 1960's electric clocks with motors in them, required more current to operate than today's modern LED and LCD clocks. The earlier appliances when operating required much more wattage to get the same job done, therefore, you will not win with this situation. good! now if all the old wiseacres would hurry up and die, we might see a higher revenue per capita in modern stuff. :-) brs, mike -- Greetings, Jerry Greenberg GLG Technologies GLG ========================================= WebPage http://www.zoom-one.com Electronics http://www.zoom-one.com/electron.htm Instruments http://www.zoom-one.com/glgtech.htm ========================================= "Watson A.Name - Watt Sun" wrote in message m... I was watching the local ABC News and they had a piece on vampire appliances. They said that an appliance could be using about 5 watts when it's turned off, and that's about $4.00 a month. This sounded a bit high to me. But since I don't get an electric bill, I have no way to tell. 5 watt-hours times 730 hours a month is 3650 watt-hours or 3.65 kWh. More than a dollar a kWh? |
#36
|
|||
|
|||
Vampire Appliances
|
#37
|
|||
|
|||
Vampire Appliances
|
#38
|
|||
|
|||
Vampire Appliances
In article , soundguy2
@worldnet.att.net says... On Mon, 06 Oct 2003 13:02:09 -0700, Lizard Blizzard wrote: Jerry G. wrote: [snip] Infact, the old 1960's electric clocks with motors in them, required more current to operate than today's modern LED and LCD clocks. The quartz sweep second hand clocks run for a year off a single AA cell. So no power at all needed from the wall outlet. The earlier appliances when operating required much more wattage to get the same job done, therefore, you will not win with this situation. One of the ladies at work replaced her old fridge with a new energy efficient one. Her electric bill went down fifty dollars a month(!) Old refrigerators and freezers wasted most of their energy in generating heat, which if in a confined room, would lower the efficiency of the unit itself, yet alone run the ambient temp of the room up to an un livable level, requiring the need for an air conditioner of some sort. the russians put their crypto vaults in little rooms and tried to cool the vault with an A/C. poor clerks didn't stay very cool and some developed leukemia from the high power noise the KGB (commo directorate branch) pumped in for anti-tempest purposes. I have a full blown media room .. full stereo system (where the main amp/pre amp is ON but display is off all the time .. phono pre amp for my Linear .. Dolby 5.1 amp set up (on all the time) 32'HDTV .. screen is the only thing that turns off, so it generates heat .. two computers (P iv's) that generate a gang of heat (did go to an LCD display which cut down on the heat from a monitor. my 21" heats a 7x12 room in winter even with the a/c unit in the window with half-assed weather seal. why do i even have double pane windows? .. but all along the back wall behind a vented folding door set is a pantry, which includes a huge side by side ref/freezer. so I have to have an 8000 btu air conditioner running 9 months out of the year. plus a Honeywell Air cleaner to keep from having to open and CLEAN everything every month! at least my CPUs have a fan to force the air through the coffee filters that keep the above implied dust out. brs, mike |
#39
|
|||
|
|||
Vampire Appliances
In article , soundguy2
@worldnet.att.net says... On Mon, 06 Oct 2003 13:02:09 -0700, Lizard Blizzard wrote: Jerry G. wrote: [snip] Infact, the old 1960's electric clocks with motors in them, required more current to operate than today's modern LED and LCD clocks. The quartz sweep second hand clocks run for a year off a single AA cell. So no power at all needed from the wall outlet. The earlier appliances when operating required much more wattage to get the same job done, therefore, you will not win with this situation. One of the ladies at work replaced her old fridge with a new energy efficient one. Her electric bill went down fifty dollars a month(!) Old refrigerators and freezers wasted most of their energy in generating heat, which if in a confined room, would lower the efficiency of the unit itself, yet alone run the ambient temp of the room up to an un livable level, requiring the need for an air conditioner of some sort. the russians put their crypto vaults in little rooms and tried to cool the vault with an A/C. poor clerks didn't stay very cool and some developed leukemia from the high power noise the KGB (commo directorate branch) pumped in for anti-tempest purposes. I have a full blown media room .. full stereo system (where the main amp/pre amp is ON but display is off all the time .. phono pre amp for my Linear .. Dolby 5.1 amp set up (on all the time) 32'HDTV .. screen is the only thing that turns off, so it generates heat .. two computers (P iv's) that generate a gang of heat (did go to an LCD display which cut down on the heat from a monitor. my 21" heats a 7x12 room in winter even with the a/c unit in the window with half-assed weather seal. why do i even have double pane windows? .. but all along the back wall behind a vented folding door set is a pantry, which includes a huge side by side ref/freezer. so I have to have an 8000 btu air conditioner running 9 months out of the year. plus a Honeywell Air cleaner to keep from having to open and CLEAN everything every month! at least my CPUs have a fan to force the air through the coffee filters that keep the above implied dust out. brs, mike |
#40
|
|||
|
|||
Vampire Appliances
In article , soundguy2
@worldnet.att.net says... On Mon, 06 Oct 2003 15:51:06 -0700, Lizard Blizzard wrote: oldsoundguy wrote: [snip] my Linear .. Dolby 5.1 amp set up (on all the time) 32'HDTV .. screen WOW! You must have a theater with a screen that big! [snip] that was the intent!! LOL. i haven't seen a big screen TV that big. not even projected. i suppose if you were really moving in relativistic terms, it would be that big, brs, mike |
Reply |
|
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Finish questions for steel kitchen appliances | Metalworking | |||
Built-in Kitchen appliances | UK diy | |||
Choosing location for kitchen appliances | UK diy | |||
|
UK diy |