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#1
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APC hums (buzzes) when hair dryer is run in another room
We live in an 80+ year old house with wiring of similar vintage (I assume).
All the computers are on UPS devices. My main computer is on an APC Back-UPS Pro 1000 with fresh batteries, which is certainly powerful enough to handle what's plugged into it. I will say that because there are no grounded outlets in this house (except for one in the kitchen), the APC unit's three-prong plug gets its 100v juice thanks to an adapter that ignores the ground prong. My stepdaughter runs a blow dryer in her room and when she does, my APC unit makes a humming buzz sound for as long as the dryer is on. The unit never beeps (as it does when there's an outage or dip in power) - it just makes this buzzing humm. Aside from whatever might be said of the lack of grounding (which cannot be helped), is this buzz indicating that any damage to the computer could be occurring? Thanks, Be |
#2
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APC hums (buzzes) when hair dryer is run in another room
"BE" wrote in message .. . We live in an 80+ year old house with wiring of similar vintage (I assume). Possibly knob and tube? Or steel conduit? My stepdaughter runs a blow dryer in her room and when she does, my APC unit makes a humming buzz sound for as long as the dryer is on. The unit never beeps (as it does when there's an outage or dip in power) - it just makes this buzzing humm. Does the dryer have a variable heat control? Aside from whatever might be said of the lack of grounding (which cannot be helped), is this buzz indicating that any damage to the computer could be occurring? Probably not. Can you meter the supply? |
#3
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APC hums (buzzes) when hair dryer is run in another room
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#4
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APC hums (buzzes) when hair dryer is run in another room
On 11/22/06 2:40 PM, in article dB29h.47$p9.5@edtnps82, "Homer J Simpson"
wrote: "BE" wrote in message .. . We live in an 80+ year old house with wiring of similar vintage (I assume). Possibly knob and tube? Or steel conduit? It is copper wire with a very thick braided covering. My stepdaughter runs a blow dryer in her room and when she does, my APC unit makes a humming buzz sound for as long as the dryer is on. The unit never beeps (as it does when there's an outage or dip in power) - it just makes this buzzing humm. Does the dryer have a variable heat control? Yes. Aside from whatever might be said of the lack of grounding (which cannot be helped), is this buzz indicating that any damage to the computer could be occurring? Probably not. Can you meter the supply? I have metered one of the outlets in another part of the house and the current seems to average 123 volts. Should I plug this tester into the back of the UPS - is that what you are suggesting? Be |
#5
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APC hums (buzzes) when hair dryer is run in another room
BE wrote:
On 11/22/06 2:40 PM, in article dB29h.47$p9.5@edtnps82, "Homer J Simpson" wrote: "BE" wrote in message .. . We live in an 80+ year old house with wiring of similar vintage (I assume). Possibly knob and tube? Or steel conduit? It is copper wire with a very thick braided covering. Single conductor or a jacketed two conductor cable? I've seen knob and tube wiring as you describe. When I got down to the actual conductor, it was something like 20 gauge...very small; and this was house mains wiring. My stepdaughter runs a blow dryer in her room and when she does, my APC unit makes a humming buzz sound for as long as the dryer is on. The unit never beeps (as it does when there's an outage or dip in power) - it just makes this buzzing humm. Does the dryer have a variable heat control? Yes. Aside from whatever might be said of the lack of grounding (which cannot be helped), is this buzz indicating that any damage to the computer could be occurring? Probably not. Can you meter the supply? I have metered one of the outlets in another part of the house and the current seems to average 123 volts. Should I plug this tester into the back of the UPS - is that what you are suggesting? Be I think he's suggesting that the load of the dryer (these can consume well over a kilowatt on high power settings) might be pulling down the supply voltage. Try again with the dryer running. It might be on the same overloaded circuit. jak |
#7
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APC hums (buzzes) when hair dryer is run in another room
BE wrote:
We live in an 80+ year old house with wiring of similar vintage (I assume). All the computers are on UPS devices. My main computer is on an APC Back-UPS Pro 1000 with fresh batteries, which is certainly powerful enough to handle what's plugged into it. I will say that because there are no grounded outlets in this house (except for one in the kitchen), the APC unit's three-prong plug gets its 100v juice thanks to an adapter that ignores the ground prong. My stepdaughter runs a blow dryer in her room and when she does, my APC unit makes a humming buzz sound for as long as the dryer is on. The unit never beeps (as it does when there's an outage or dip in power) - it just makes this buzzing humm. Aside from whatever might be said of the lack of grounding (which cannot be helped), is this buzz indicating that any damage to the computer could be occurring? Thanks, Be Measure the voltage at the outlet the UPS is plugged into while the hair dryer is on, it sounds like the voltage is sagging. |
#8
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APC hums (buzzes) when hair dryer is run in another room
"BE" wrote in message .. . Possibly knob and tube? Or steel conduit? It is copper wire with a very thick braided covering. Does it run in steel conduit? If so, that is often (but not always IME) a good ground. Does the dryer have a variable heat control? Yes. Just a switch (low-med-high) or a dial (0-9)? I have metered one of the outlets in another part of the house and the current seems to average 123 volts. Should I plug this tester into the back of the UPS - is that what you are suggesting? No, while there is a niggling doubt that something nasty is happening you are most probably OK. However your wiring was intended for lighting and very light loads (radio etc). I assume you have gas cooking and heating and not electric. If you have a friendly electrician perhaps he could tell you his opinion of your wiring. |
#9
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APC hums (buzzes) when hair dryer is run in another room
On 11/22/06 7:24 PM, in article XK69h.89$p9.21@edtnps82, "Homer J Simpson"
wrote: "BE" wrote in message .. . Possibly knob and tube? Or steel conduit? It is copper wire with a very thick braided covering. Does it run in steel conduit? If so, that is often (but not always IME) a good ground. Does the dryer have a variable heat control? Yes. Just a switch (low-med-high) or a dial (0-9)? I have metered one of the outlets in another part of the house and the current seems to average 123 volts. Should I plug this tester into the back of the UPS - is that what you are suggesting? No, while there is a niggling doubt that something nasty is happening you are most probably OK. However your wiring was intended for lighting and very light loads (radio etc). I assume you have gas cooking and heating and not electric. If you have a friendly electrician perhaps he could tell you his opinion of your wiring. I _think_ we are OK - we have lived in this house for more than 10 years now; if we were overtaxing the circuits they would have done something (logic suggests) to indicate this by now. Only on a couple occasions have we even blown a fuse. Our fuses are the old screw-in type that look like the bottoms of light bulbs. Be |
#10
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APC hums (buzzes) when hair dryer is run in another room
"BE" wrote in message .. . However your wiring was intended for lighting and very light loads (radio etc). I assume you have gas cooking and heating and not electric. If you have a friendly electrician perhaps he could tell you his opinion of your wiring. I _think_ we are OK - we have lived in this house for more than 10 years now; if we were overtaxing the circuits they would have done something (logic suggests) to indicate this by now. Only on a couple occasions have we even blown a fuse. Our fuses are the old screw-in type that look like the bottoms of light bulbs. I hear you, but sometimes people screw with this stuff. Knob and tube is usually fine unless you get an amateur who tinkers with it. Then it is a fire and shock risk. |
#11
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APC hums (buzzes) when hair dryer is run in another room
BE wrote: We live in an 80+ year old house with wiring of similar vintage (I assume). All the computers are on UPS devices. My main computer is on an APC Back-UPS Pro 1000 with fresh batteries, which is certainly powerful enough to handle what's plugged into it. I will say that because there are no grounded outlets in this house (except for one in the kitchen), the APC unit's three-prong plug gets its 100v juice thanks to an adapter that ignores the ground prong. My stepdaughter runs a blow dryer in her room and when she does, my APC unit makes a humming buzz sound for as long as the dryer is on. The unit never beeps (as it does when there's an outage or dip in power) - it just makes this buzzing humm. Aside from whatever might be said of the lack of grounding (which cannot be helped), is this buzz indicating that any damage to the computer could be occurring? Thanks, Be I think there is a very simple explanation for what is going on. The hairdryer is putting out a lot of electrical "noise" onto the electrical power line. That noise goes through the wiring and into the front end of the UPC and gets into the UPC power line voltage sensors and is causing them to rapidly cycle on and off, hence the chattering or buzzing sound from the UPC. I would guess that the dryer and the UPC are on the same circuit, or at least on the same 120V phase, assuming the house does have a 230V input. The noise is most likely being conducted into the UPC, although I would not 100% rule out radiated noise. A simple power line filter on either the hair dryer or the UPC should fix the problem. They are about the size of a pack of cigarettes, plug into the wall and have an outlet into which you plug the appliance. You can also make up a crude filter using ferrite toroidal cores. If you can get hold of a member of the Institute of Electrical and Electronic Engineers Electromagnetic Compatibility Society, they can help you. I am past president of that organization and our members are always interested in these sorts of problems. H. R. (Bob) Hofmann |
#12
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APC hums (buzzes) when hair dryer is run in another room
"BE" wrote in message
.. . On 11/22/06 7:24 PM, in article XK69h.89$p9.21@edtnps82, "Homer J Simpson" wrote: "BE" wrote in message .. . Possibly knob and tube? Or steel conduit? It is copper wire with a very thick braided covering. Does it run in steel conduit? If so, that is often (but not always IME) a good ground. Does the dryer have a variable heat control? Yes. Just a switch (low-med-high) or a dial (0-9)? I have metered one of the outlets in another part of the house and the current seems to average 123 volts. Should I plug this tester into the back of the UPS - is that what you are suggesting? No, while there is a niggling doubt that something nasty is happening you are most probably OK. However your wiring was intended for lighting and very light loads (radio etc). I assume you have gas cooking and heating and not electric. If you have a friendly electrician perhaps he could tell you his opinion of your wiring. I _think_ we are OK - we have lived in this house for more than 10 years now; if we were overtaxing the circuits they would have done something (logic suggests) to indicate this by now. Only on a couple occasions have we even blown a fuse. Our fuses are the old screw-in type that look like the bottoms of light bulbs. Be My house is 100 years old. My K&T is 16 gauge. I've replaced all of the power circuits in the house. Only using the K&T for lighting and replaced most of the lights with CFL. The hair dryer is going to take a considerable portion of the lines capacity. Do you know if the fuse is correct for the wiring? Even if it is correct a bad connection can cause heat and fire without blowing fuse. Not only are the lines light duty, to say the least, little thought was given as to where power needed to be distributed. Especially by modern standards. The outlet we used for coffeemaker and toaster was 10' from fuse box but electricity came through 60' wire. Not trying to scare you but you really should know what your dealing with regardless of what's causing the noise. What you describe doesn't sound like arcing but who knows. House fires are almost as common as major crimes. Do you lock your doors at night? |
#13
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APC hums (buzzes) when hair dryer is run in another room
BE wrote: We live in an 80+ year old house with wiring of similar vintage (I assume). All the computers are on UPS devices. My main computer is on an APC Back-UPS Pro 1000 with fresh batteries, which is certainly powerful enough to handle what's plugged into it. I will say that because there are no grounded outlets in this house (except for one in the kitchen), the APC unit's three-prong plug gets its 100v juice thanks to an adapter that ignores the ground prong. My stepdaughter runs a blow dryer in her room and when she does, my APC unit makes a humming buzz sound for as long as the dryer is on. The unit never beeps (as it does when there's an outage or dip in power) - it just makes this buzzing humm. Aside from whatever might be said of the lack of grounding (which cannot be helped), is this buzz indicating that any damage to the computer could be occurring? Does it only do it when the hair dryer's on low heat ? I've come across something similar *once only ever* and it was also bad wiring. The hairdryer uses a diode for low heat and this creates a DC content on the AC line. You need your wiring replaced. Graham |
#14
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APC hums (buzzes) when hair dryer is run in another room
"Meat Plow" wrote in message news Ok what's knob and tube? http://en.wikipedia.org/wiki/Knob_and_tube_wiring |
#15
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APC hums (buzzes) when hair dryer is run in another room
Meat Plow wrote:
Ok what's knob and tube? http://en.wikipedia.org/wiki/Knob_and_tube_wiring -- Service to my country? Been there, Done that, and I've got my DD214 to prove it. Member of DAV #85. Michael A. Terrell Central Florida |
#16
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APC hums (buzzes) when hair dryer is run in another room
Meat Plow wrote:
snip My home lacks 3 conductor wiring. I added a ground to a few outlets (computers, ham equipment uninterruptable supplies, shop electronics) by driving a 6" copper rod at each end of the house into the ground and then adding them to whatever circuit I wanted. snip Try to convince me that was a good idea. My first reaction is to think it would potentially (no pun intended) create a colossal ground loop. -- The e-mail address in our reply-to line is reversed in an attempt to minimize spam. Our true address is of the form . |
#17
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APC hums (buzzes) when hair dryer is run in another room
APC is probably sensing all the spikes and noise being generated by the hair
dryer, that is across the ac line. apc units can be so well designed that they will detect any non-pure waveform that gets induced into the circuit it is connected to. they usually switch to battery whenever this happens, they do it so quickly u nevr notice unless it is a repeated event, such as a 1.2kw hair dryer and its cheap motor loading the wires in your house. while it wont cause you any problems, it is an indication the house wiring is inadequate for the powerful hair dryer i am surprised the APC even works without a proper ground circuit! most will fail to start when ungrounded. "BE" wrote in message .. . We live in an 80+ year old house with wiring of similar vintage (I assume).use you any problems, All the computers are on UPS devices. My main computer is on an APC Back-UPS Pro 1000 with fresh batteries, which is certainly powerful enough to handle what's plugged into it. I will say that because there are no grounded outlets in this house (except for one in the kitchen), the APC unit's three-prong plug gets its 100v juice thanks to an adapter that ignores the ground prong. My stepdaughter runs a blow dryer in her room and when she does, my APC unit makes a humming buzz sound for as long as the dryer is on. The unit never beeps (as it does when there's an outage or dip in power) - it just makes this buzzing humm. Aside from whatever might be said of the lack of grounding (which cannot be helped), is this buzz indicating that any damage to the computer could be occurring? Thanks, Be |
#18
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APC hums (buzzes) when hair dryer is run in another room
Hi!
My stepdaughter runs a blow dryer in her room and when she does, my APC unit makes a humming buzz sound for as long as the dryer is on. It's probably nothing to worry about. I had a PS/2 Model 80 whose power supply made a noticeable buzzing noise every time the power floor cleaner attachment was used on a household vacuum. What you are probably hearing is the vibration of a transformer. I don't know specifically about the Back-UPS Pro models, but the Smart UPS and Back UPS RS models have voltage correction circuits built into them. These can adjust high or low line voltage without going to battery. Your unit could be doing this. If it is, you won't hear any beeping. The only sign of it is an entry in the PowerChute software--if you are using that and have a version that keeps an event log. (PowerChute Plus and the APC network management cards (only for the Smart-UPS) do have an event log. I don't know about PowerChute Personal or Business editions.) I don't think you'll find that any damage is happening to the UPS or your computer. However, you really should try to ground the UPS somehow. For its internal surge protection to be effective, you may have to do so. William |
#19
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APC hums (buzzes) when hair dryer is run in another room
In article ,
(known to some as BE) scribed... bigsnip I would love to be able to ground it properly, but this is not possible. I figure it is better than running the computers themselves ungrounded and subject to this house's "dirty" electricity. Since I lost a computer 7-8 years ago to the abuse this house's electricity inflicted upon its power supply, I have made it a policy to have a UPS for everything I care about: snippety-two You really, REALLY need to run new wiring if you expect to be able to safely run modern equipment. If I were in your situation, I wouldn't run anything more modern than a desk lamp until I'd brought everything up to current code. No UPS was ever designed to run ungrounded. I won't be at all surprised if the APC's 'Site Wiring Fault' warning light is on continuously. At the very least, you need to run a proper ground for the thing, and that will also have the effect of properly grounding everything you attach to it. With an eventual upgrade in mind: Many states allow homeowners to do their own electrical work IF it is inspected after said work is done. Honestly, it's not that hard. I replaced our entire breaker panel (upgraded from 125-amp main to 200), and it passed inspection on the first try. Your biggest issues are to use approved wire (non-metallic sheath cable, recommend #12 all around so you can do 20-amp outlets by default), and to make sure whatever breaker panel replaces the fuse box has enough spots for everything you want to do. Do yourself a favor: Ground that APC now, and make upgrading the house wiring a major priority. Happy tweaking. -- Dr. Anton T. Squeegee, Director, Dutch Surrealist Plumbing Institute (Known to some as Bruce Lane, KC7GR) http://www.bluefeathertech.com -- kyrrin a/t bluefeathertech d-o=t calm "Salvadore Dali's computer has surreal ports..." |
#20
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APC hums (buzzes) when hair dryer is run in another room
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#21
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APC hums (buzzes) when hair dryer is run in another room
"CJT" wrote in message ... Try to convince me that was a good idea. My first reaction is to think it would potentially (no pun intended) create a colossal ground loop. It is rare indeed that no ground beats a good solid one. |
#22
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APC hums (buzzes) when hair dryer is run in another room
"BE" wrote in message .. . Yes, that light is continuously on. I will search Google for instructions of how to prepare a ground. DON'T ground to a gas pipe! Your library will have a code book - well worth reading on grounding. |
#23
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APC hums (buzzes) when hair dryer is run in another room
Homer J Simpson wrote:
"CJT" wrote in message ... Try to convince me that was a good idea. My first reaction is to think it would potentially (no pun intended) create a colossal ground loop. It is rare indeed that no ground beats a good solid one. While true, I'm not sure that "good solid" applies to the ground system described (i.e. rods driven into the earth on opposite ends of a house, each grounding a portion of the outlets in said house). -- The e-mail address in our reply-to line is reversed in an attempt to minimize spam. Our true address is of the form . |
#24
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APC hums (buzzes) when hair dryer is run in another room
"CJT" wrote in message ... While true, I'm not sure that "good solid" applies to the ground system described (i.e. rods driven into the earth on opposite ends of a house, each grounding a portion of the outlets in said house). A ground rod is often a good ground unless the soil is very poor and dry. |
#25
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APC hums (buzzes) when hair dryer is run in another room
i am surprised the APC even works without a proper ground circuit! most will fail to start when ungrounded. Sorry but you are incorrect. I have used various APC UPS models from a smart-ups 300 to a 1500, an old APC power cell model, and also APC Back-UPS 1200 and a Back-ups pro 500 without a ground. All of these models will function without a ground. |
#26
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APC hums (buzzes) when hair dryer is run in another room
mine has light that indicates "Grounded". when it is initially plugged in
and the light is out, the thing doesnt run. even with full battery charge. "Michael Kennedy" wrote in message ... i am surprised the APC even works without a proper ground circuit! most will fail to start when ungrounded. Sorry but you are incorrect. I have used various APC UPS models from a smart-ups 300 to a 1500, an old APC power cell model, and also APC Back-UPS 1200 and a Back-ups pro 500 without a ground. All of these models will function without a ground. |
#27
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APC hums (buzzes) when hair dryer is run in another room
huh.. what model do you have?
wrote in message om... mine has light that indicates "Grounded". when it is initially plugged in and the light is out, the thing doesnt run. even with full battery charge. "Michael Kennedy" wrote in message ... i am surprised the APC even works without a proper ground circuit! most will fail to start when ungrounded. Sorry but you are incorrect. I have used various APC UPS models from a smart-ups 300 to a 1500, an old APC power cell model, and also APC Back-UPS 1200 and a Back-ups pro 500 without a ground. All of these models will function without a ground. |
#28
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APC hums (buzzes) when hair dryer is run in another room
Oh and by the way on all of mine the wiring fault light lights up when
ungrounded, but they still function. Maybe your model is newer than all of mine and they have changed how they work. Thats intresting that they changed that, but it also makes good sense. - Mike "Michael Kennedy" wrote in message ... huh.. what model do you have? wrote in message om... mine has light that indicates "Grounded". when it is initially plugged in and the light is out, the thing doesnt run. even with full battery charge. "Michael Kennedy" wrote in message ... i am surprised the APC even works without a proper ground circuit! most will fail to start when ungrounded. Sorry but you are incorrect. I have used various APC UPS models from a smart-ups 300 to a 1500, an old APC power cell model, and also APC Back-UPS 1200 and a Back-ups pro 500 without a ground. All of these models will function without a ground. |
#29
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APC hums (buzzes) when hair dryer is run in another room
Michael Kennedy wrote:
Oh and by the way on all of mine the wiring fault light lights up when ungrounded, but they still function. Maybe your model is newer than all of mine and they have changed how they work. Thats intresting that they changed that, but it also makes good sense. I think he said the ground light comes on while the unit is POSTing, then goes out. During that period of time, there is no output. He didn't say it wouldn't operate without a ground, and doesn't indicate that he's ever tried it that way. He's attributing the ground light issue with an actual *grounding* issue. jak - Mike "Michael Kennedy" wrote in message ... huh.. what model do you have? wrote in message om... mine has light that indicates "Grounded". when it is initially plugged in and the light is out, the thing doesnt run. even with full battery charge. "Michael Kennedy" wrote in message ... i am surprised the APC even works without a proper ground circuit! most will fail to start when ungrounded. Sorry but you are incorrect. I have used various APC UPS models from a smart-ups 300 to a 1500, an old APC power cell model, and also APC Back-UPS 1200 and a Back-ups pro 500 without a ground. All of these models will function without a ground. |
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