My old inverter worked flawlessly. It's rated at 300 watts (Peak), which
means it's really 150 or 200W. A local second hand store had a 400W
(RMS) inverter. The store owner said he's not sure if it works, and he
told me to take it out to my car and plug it in. I plugged it in, and
the moment I turned on it's power switch, it blew the 15A fuse to the
cig lighter in my car. (Nothing was plugged into the 110VAC output).

The store owner knows me, and he told me to take it home and see if I
can get it to work, and if it does, give him $5, if not, just bring it
back. I put a multimeter across the 12V input leads, and get around 500
ohms, which rises over time. I opened it up, and found it has a 25A
built in fuse. This makes me wonder if it requires 25A to work, even
with no load?????

My question is this: How much current is required for these inverters,
depending on their wattage rating? I have never seen any of them with
the required input amperage listed on them?

While looking on ebay, I noticed a lot of then rated at 2000, 4000, and
even higher wattage. In fact I saw one listed at 16,000 watts. Obviously
these high powered ones need to be hard wired to the car battery (not
using the cig lighter socket), but I can not see how any car battery or
alternator could handle a 16,000 watt unit.

I had no luck looking for a website that shows the rated input amps for
inverters, based on their output power.

On Saturday, 14 October 2017 23:20:12 UTC+1, wrote:

My old inverter worked flawlessly. It's rated at 300 watts (Peak), which
means it's really 150 or 200W. A local second hand store had a 400W
(RMS) inverter. The store owner said he's not sure if it works, and he
told me to take it out to my car and plug it in. I plugged it in, and
the moment I turned on it's power switch, it blew the 15A fuse to the
cig lighter in my car. (Nothing was plugged into the 110VAC output).

The store owner knows me, and he told me to take it home and see if I
can get it to work, and if it does, give him $5, if not, just bring it
back. I put a multimeter across the 12V input leads, and get around 500
ohms, which rises over time. I opened it up, and found it has a 25A
built in fuse. This makes me wonder if it requires 25A to work, even
with no load?????

of course not

My question is this: How much current is required for these inverters,
depending on their wattage rating? I have never seen any of them with
the required input amperage listed on them?

calculate from output load wattage assuming around 90% efficient will get you an approx answer. It'll be more than that offload though.

While looking on ebay, I noticed a lot of then rated at 2000, 4000, and
even higher wattage. In fact I saw one listed at 16,000 watts. Obviously
these high powered ones need to be hard wired to the car battery (not
using the cig lighter socket), but I can not see how any car battery or
alternator could handle a 16,000 watt unit.

real watts or chinglish microwatts?

I had no luck looking for a website that shows the rated input amps for
inverters, based on their output power.


NT

wrote on 10/14/2017 6:19 PM:
My old inverter worked flawlessly. It's rated at 300 watts (Peak), which
means it's really 150 or 200W. A local second hand store had a 400W
(RMS) inverter. The store owner said he's not sure if it works, and he
told me to take it out to my car and plug it in. I plugged it in, and
the moment I turned on it's power switch, it blew the 15A fuse to the
cig lighter in my car. (Nothing was plugged into the 110VAC output).

The store owner knows me, and he told me to take it home and see if I
can get it to work, and if it does, give him $5, if not, just bring it
back. I put a multimeter across the 12V input leads, and get around 500
ohms, which rises over time. I opened it up, and found it has a 25A
built in fuse. This makes me wonder if it requires 25A to work, even
with no load?????

You are probably looking at a surge current to charge caps somewhere. If
they aren't directly on the input, the unit won't draw much current until it
sees enough voltage to power up. Then it starts drawing a surge to charge
the caps and pop goes the fuse. I know appliance fuses come in slow blow
and fast blow, but I don't think I've ever seen a fast blow automotive fuse.
They have a lot less thermal mass to heat up. All the automotive fuses
I've seen had fairly fat links.


My question is this: How much current is required for these inverters,
depending on their wattage rating? I have never seen any of them with
the required input amperage listed on them?

While looking on ebay, I noticed a lot of then rated at 2000, 4000, and
even higher wattage. In fact I saw one listed at 16,000 watts. Obviously
these high powered ones need to be hard wired to the car battery (not
using the cig lighter socket), but I can not see how any car battery or
alternator could handle a 16,000 watt unit.

Do you believe everything you read? 16,000 watts is 21 horsepower. Really?
21 horsepower in an inverter? Is it as big as a suitcase and have a big
fan to keep it cool? From 12 volts that would be 1,333 amps. Yeah, right!

--

Rick C

Viewed the eclipse at Wintercrest Farms,
on the centerline of totality since 1998

On Sunday, 15 October 2017 02:04:20 UTC+1, rickman wrote:
wrote on 10/14/2017 6:19 PM:

My old inverter worked flawlessly. It's rated at 300 watts (Peak), which
means it's really 150 or 200W. A local second hand store had a 400W
(RMS) inverter. The store owner said he's not sure if it works, and he
told me to take it out to my car and plug it in. I plugged it in, and
the moment I turned on it's power switch, it blew the 15A fuse to the
cig lighter in my car. (Nothing was plugged into the 110VAC output).

The store owner knows me, and he told me to take it home and see if I
can get it to work, and if it does, give him $5, if not, just bring it
back. I put a multimeter across the 12V input leads, and get around 500
ohms, which rises over time. I opened it up, and found it has a 25A
built in fuse. This makes me wonder if it requires 25A to work, even
with no load?????

You are probably looking at a surge current to charge caps somewhere. If
they aren't directly on the input, the unit won't draw much current until it
sees enough voltage to power up. Then it starts drawing a surge to charge
the caps and pop goes the fuse. I know appliance fuses come in slow blow
and fast blow, but I don't think I've ever seen a fast blow automotive fuse.
They have a lot less thermal mass to heat up. All the automotive fuses
I've seen had fairly fat links.


My question is this: How much current is required for these inverters,
depending on their wattage rating? I have never seen any of them with
the required input amperage listed on them?

While looking on ebay, I noticed a lot of then rated at 2000, 4000, and
even higher wattage. In fact I saw one listed at 16,000 watts. Obviously
these high powered ones need to be hard wired to the car battery (not
using the cig lighter socket), but I can not see how any car battery or
alternator could handle a 16,000 watt unit.

Do you believe everything you read? 16,000 watts is 21 horsepower. Really?
21 horsepower in an inverter? Is it as big as a suitcase and have a big
fan to keep it cool? From 12 volts that would be 1,333 amps. Yeah, right!

May as well just connect the batteries in series to get 120 or 240v. If you want ac, just swap the leads over really fast


NT

wrote:

My old inverter worked flawlessly. It's rated at 300 watts (Peak), which
means it's really 150 or 200W. A local second hand store had a 400W
(RMS) inverter. The store owner said he's not sure if it works, and he
told me to take it out to my car and plug it in. I plugged it in, and
the moment I turned on it's power switch, it blew the 15A fuse to the
cig lighter in my car. (Nothing was plugged into the 110VAC output).

The store owner knows me, and he told me to take it home and see if I
can get it to work, and if it does, give him $5, if not, just bring it
back. I put a multimeter across the 12V input leads, and get around 500
ohms, which rises over time. I opened it up, and found it has a 25A
built in fuse. This makes me wonder if it requires 25A to work, even
with no load?????

400 W requires 33.33 A at 100% efficiency. So, it could not possibly be a
400 W inverter. But, maybe 400 W peak, for a very short peak.
My question is this: How much current is required for these inverters,
depending on their wattage rating? I have never seen any of them with
the required input amperage listed on them?

While looking on ebay, I noticed a lot of then rated at 2000, 4000, and
even higher wattage. In fact I saw one listed at 16,000 watts.
16 KW? That will need 1333 A at 100% efficiency. No WAY would anyone ever
build a 16 KW inverter that ran off 12 V DC. More like 120 V DC input.

Obviously
these high powered ones need to be hard wired to the car battery (not
using the cig lighter socket), but I can not see how any car battery or
alternator could handle a 16,000 watt unit.

I had no luck looking for a website that shows the rated input amps for
inverters, based on their output power.
You don't NEED a web site! Watts / V = current! VERY simple calculation,
(when ignoring efficiency.)

Jon

In sci.electronics.repair, on Sat, 14 Oct 2017 21:04:16 -0400, rickman
wrote:

wrote on 10/14/2017 6:19 PM:
My old inverter worked flawlessly. It's rated at 300 watts (Peak), which
means it's really 150 or 200W. A local second hand store had a 400W
(RMS) inverter. The store owner said he's not sure if it works, and he
told me to take it out to my car and plug it in. I plugged it in, and
the moment I turned on it's power switch, it blew the 15A fuse to the
cig lighter in my car. (Nothing was plugged into the 110VAC output).

The store owner knows me, and he told me to take it home and see if I
can get it to work, and if it does, give him $5, if not, just bring it
back. I put a multimeter across the 12V input leads, and get around 500
ohms, which rises over time. I opened it up, and found it has a 25A
built in fuse. This makes me wonder if it requires 25A to work, even
with no load?????

You are probably looking at a surge current to charge caps somewhere. If
they aren't directly on the input, the unit won't draw much current until it
sees enough voltage to power up. Then it starts drawing a surge to charge
the caps and pop goes the fuse. I know appliance fuses come in slow blow
and fast blow, but I don't think I've ever seen a fast blow automotive fuse.
They have a lot less thermal mass to heat up. All the automotive fuses
I've seen had fairly fat links.


My question is this: How much current is required for these inverters,
depending on their wattage rating? I have never seen any of them with
the required input amperage listed on them?

While looking on ebay, I noticed a lot of then rated at 2000, 4000, and
even higher wattage. In fact I saw one listed at 16,000 watts. Obviously
these high powered ones need to be hard wired to the car battery (not
using the cig lighter socket), but I can not see how any car battery or
alternator could handle a 16,000 watt unit.

Do you believe everything you read? 16,000 watts is 21 horsepower. Really?
21 horsepower in an inverter? Is it as big as a suitcase and have a big
fan to keep it cool? From 12 volts that would be 1,333 amps. Yeah, right!

That's not difficult if you have a 10,000 Ahr battery.

On Sat, 14 Oct 2017 22:17:24 -0500, Jon Elson
wrote:

wrote:

My old inverter worked flawlessly. It's rated at 300 watts (Peak), which
means it's really 150 or 200W. A local second hand store had a 400W
(RMS) inverter. The store owner said he's not sure if it works, and he
told me to take it out to my car and plug it in. I plugged it in, and
the moment I turned on it's power switch, it blew the 15A fuse to the
cig lighter in my car. (Nothing was plugged into the 110VAC output).

The store owner knows me, and he told me to take it home and see if I
can get it to work, and if it does, give him $5, if not, just bring it
back. I put a multimeter across the 12V input leads, and get around 500
ohms, which rises over time. I opened it up, and found it has a 25A
built in fuse. This makes me wonder if it requires 25A to work, even
with no load?????

400 W requires 33.33 A at 100% efficiency. So, it could not possibly be a
400 W inverter. But, maybe 400 W peak, for a very short peak.
My question is this: How much current is required for these inverters,
depending on their wattage rating? I have never seen any of them with
the required input amperage listed on them?

While looking on ebay, I noticed a lot of then rated at 2000, 4000, and
even higher wattage. In fact I saw one listed at 16,000 watts.
16 KW? That will need 1333 A at 100% efficiency. No WAY would anyone ever
build a 16 KW inverter that ran off 12 V DC. More like 120 V DC input.

Obviously
these high powered ones need to be hard wired to the car battery (not
using the cig lighter socket), but I can not see how any car battery or
alternator could handle a 16,000 watt unit.

I had no luck looking for a website that shows the rated input amps for
inverters, based on their output power.
You don't NEED a web site! Watts / V = current! VERY simple calculation,
(when ignoring efficiency.)

Jon

It says on it, 400 Watts continuous, 800 Watts Peak. Your calculation
matches the formula you posted. In that case, if it needs 33.33A to
operate at full load, that built in 25A fuse wont handle it.

But I connected it to my car with NO load. Why did it blow the 15A fuse
in my car? Obviously it's not dead shorted. My multimeter shows around
500ohms on the 12V input, (which climbs over time).

Since I posted this message, I connected it directly to a car battery
using jumper cables. It threw a large spark (with power switch turned
on), as I touched the cable to the battery. Then it appeared to work. I
did not attach any 120VAC device to it yet, because the weather is too
rainy to mess with it outdoors. But the LED indicator showed it to be
working.

wrote:

-------------------------


It says on it, 400 Watts continuous, 800 Watts Peak. Your calculation
matches the formula you posted. In that case, if it needs 33.33A to
operate at full load, that built in 25A fuse wont handle it.

But I connected it to my car with NO load. Why did it blow the 15A fuse
in my car? Obviously it's not dead shorted. My multimeter shows around
500ohms on the 12V input, (which climbs over time).

Since I posted this message, I connected it directly to a car battery
using jumper cables. It threw a large spark (with power switch turned
on), as I touched the cable to the battery. Then it appeared to work. I
did not attach any 120VAC device to it yet, because the weather is too
rainy to mess with it outdoors. But the LED indicator showed it to be
working.



** Likely an "inrush" surge with the first cycle of drive to the output transformer. You said it was "old" so I bet it's heavy too, using an iron transformer to produce 120V AC output.

When 12V DC is applied, the drive circuit applies it directly to the low voltage primary causing the core to briefly until steady AC drive conditions arrive.


..... Phil

On Sunday, 15 October 2017 05:25:29 UTC+1, wrote:
On Sat, 14 Oct 2017 22:17:24 -0500, Jon Elson
wrote:

wrote:

My old inverter worked flawlessly. It's rated at 300 watts (Peak), which
means it's really 150 or 200W. A local second hand store had a 400W
(RMS) inverter. The store owner said he's not sure if it works, and he
told me to take it out to my car and plug it in. I plugged it in, and
the moment I turned on it's power switch, it blew the 15A fuse to the
cig lighter in my car. (Nothing was plugged into the 110VAC output).

The store owner knows me, and he told me to take it home and see if I
can get it to work, and if it does, give him $5, if not, just bring it
back. I put a multimeter across the 12V input leads, and get around 500
ohms, which rises over time. I opened it up, and found it has a 25A
built in fuse. This makes me wonder if it requires 25A to work, even
with no load?????

400 W requires 33.33 A at 100% efficiency. So, it could not possibly be a
400 W inverter. But, maybe 400 W peak, for a very short peak.
My question is this: How much current is required for these inverters,
depending on their wattage rating? I have never seen any of them with
the required input amperage listed on them?

While looking on ebay, I noticed a lot of then rated at 2000, 4000, and
even higher wattage. In fact I saw one listed at 16,000 watts.
16 KW? That will need 1333 A at 100% efficiency. No WAY would anyone ever
build a 16 KW inverter that ran off 12 V DC. More like 120 V DC input.

Obviously
these high powered ones need to be hard wired to the car battery (not
using the cig lighter socket), but I can not see how any car battery or
alternator could handle a 16,000 watt unit.

I had no luck looking for a website that shows the rated input amps for
inverters, based on their output power.
You don't NEED a web site! Watts / V = current! VERY simple calculation,
(when ignoring efficiency.)

Jon

It says on it, 400 Watts continuous, 800 Watts Peak. Your calculation
matches the formula you posted. In that case, if it needs 33.33A to
operate at full load, that built in 25A fuse wont handle it.

But I connected it to my car with NO load. Why did it blow the 15A fuse
in my car? Obviously it's not dead shorted. My multimeter shows around
500ohms on the 12V input, (which climbs over time).

Since I posted this message, I connected it directly to a car battery
using jumper cables. It threw a large spark (with power switch turned
on), as I touched the cable to the battery. Then it appeared to work. I
did not attach any 120VAC device to it yet, because the weather is too
rainy to mess with it outdoors. But the LED indicator showed it to be
working.

Invertors aren't 100% efficient, so 37A draw is more likely at 400w out. A 25A fuse will pass that for a fair while.


NT

On Sat, 14 Oct 2017 23:25:13 -0500, wrote:

On Sat, 14 Oct 2017 22:17:24 -0500, Jon Elson
wrote:

wrote:

My old inverter worked flawlessly. It's rated at 300 watts (Peak), which
means it's really 150 or 200W. A local second hand store had a 400W
(RMS) inverter. The store owner said he's not sure if it works, and he
told me to take it out to my car and plug it in. I plugged it in, and
the moment I turned on it's power switch, it blew the 15A fuse to the
cig lighter in my car. (Nothing was plugged into the 110VAC output).

The store owner knows me, and he told me to take it home and see if I
can get it to work, and if it does, give him $5, if not, just bring it
back. I put a multimeter across the 12V input leads, and get around 500
ohms, which rises over time. I opened it up, and found it has a 25A
built in fuse. This makes me wonder if it requires 25A to work, even
with no load?????

400 W requires 33.33 A at 100% efficiency. So, it could not possibly be a
400 W inverter. But, maybe 400 W peak, for a very short peak.
My question is this: How much current is required for these inverters,
depending on their wattage rating? I have never seen any of them with
the required input amperage listed on them?

While looking on ebay, I noticed a lot of then rated at 2000, 4000, and
even higher wattage. In fact I saw one listed at 16,000 watts.
16 KW? That will need 1333 A at 100% efficiency. No WAY would anyone ever
build a 16 KW inverter that ran off 12 V DC. More like 120 V DC input.

Obviously
these high powered ones need to be hard wired to the car battery (not
using the cig lighter socket), but I can not see how any car battery or
alternator could handle a 16,000 watt unit.

I had no luck looking for a website that shows the rated input amps for
inverters, based on their output power.
You don't NEED a web site! Watts / V = current! VERY simple calculation,
(when ignoring efficiency.)

Jon

It says on it, 400 Watts continuous, 800 Watts Peak. Your calculation
matches the formula you posted. In that case, if it needs 33.33A to
operate at full load, that built in 25A fuse wont handle it.

But I connected it to my car with NO load. Why did it blow the 15A fuse
in my car? Obviously it's not dead shorted. My multimeter shows around
500ohms on the 12V input, (which climbs over time).

Since I posted this message, I connected it directly to a car battery
using jumper cables. It threw a large spark (with power switch turned
on), as I touched the cable to the battery. Then it appeared to work. I
did not attach any 120VAC device to it yet, because the weather is too
rainy to mess with it outdoors. But the LED indicator showed it to be
working.

It probably blew the fuse because the inrush current to charge the
caps was too high for the 15 amp fuse. There are ways to limit the
inrush current. I know that the inverter drives for my machine tool
spindles limit this current somehow. The manuals for each machine
mention this feature. There is a lag in the machines between powering
up and when drives signal the control that they are ready. Or in the
case of the inverter based welder when the internal contactor for the
welding output is enabled. There isn't a big spike in current draw
when it powers up or when welding commences. It ramps up the welding
current once the arc is established.
Eric

On Sun, 15 Oct 2017 11:41:06 -0700, wrote:



It says on it, 400 Watts continuous, 800 Watts Peak. Your calculation
matches the formula you posted. In that case, if it needs 33.33A to
operate at full load, that built in 25A fuse wont handle it.

But I connected it to my car with NO load. Why did it blow the 15A fuse
in my car? Obviously it's not dead shorted. My multimeter shows around
500ohms on the 12V input, (which climbs over time).

Since I posted this message, I connected it directly to a car battery
using jumper cables. It threw a large spark (with power switch turned
on), as I touched the cable to the battery. Then it appeared to work. I
did not attach any 120VAC device to it yet, because the weather is too
rainy to mess with it outdoors. But the LED indicator showed it to be
working.

It probably blew the fuse because the inrush current to charge the
caps was too high for the 15 amp fuse. There are ways to limit the
inrush current. I know that the inverter drives for my machine tool
spindles limit this current somehow. The manuals for each machine
mention this feature. There is a lag in the machines between powering
up and when drives signal the control that they are ready. Or in the
case of the inverter based welder when the internal contactor for the
welding output is enabled. There isn't a big spike in current draw
when it powers up or when welding commences. It ramps up the welding
current once the arc is established.
Eric

I sort of thought the same thing. But when I connected it directly to a
battery, using auto jumper cables, as soon as I touched the POS cable to
the battery, I got heavy sparking, so I pulled the cable off the
battery. That's when I noticed the inverter's switch was in the OFF
position. With the battery still disconnected, I flipped the switch on
the ON position, and the LEDs on the front of it, lit up for a few
seconds. Thus, some capacitor became charged up, and it's stored charge,
caused the LED to light.

At that point, I thought that this inverter is just too big for plugging
it into a cig lighter. (My old inverter which is no longer working, was
rated at 300W peak, and continuous power is 125W. That never blew any
fuses).

So, I visited a friend the next day, and was telling him about this,
when he grabbed his inverter and plugged it into my car's cig lighter
socket. It worked perfectly. His inverter is rated at 700W continuous ,
or 1400W peak. So, if his 700W cont. works fine, my 400W cont. should
not cause any problems.

The seller of that thing told me to just throw it in the trash, if it
blows fuses. Of course I wont throw it in trash, and now I am more
curious why it blows fuses and why it throws large sparks when it's
turned OFF.

The bad thing is that they dont put schematics online for them. At least
I cant find one. It's a Cobra CPI 480 model.

On Tuesday, October 17, 2017 at 12:33:46 AM UTC-4, wrote:

I sort of thought the same thing. But when I connected it directly to a
battery, using auto jumper cables, as soon as I touched the POS cable to
the battery, I got heavy sparking, so I pulled the cable off the
battery. That's when I noticed the inverter's switch was in the OFF
position. With the battery still disconnected, I flipped the switch on
the ON position, and the LEDs on the front of it, lit up for a few
seconds. Thus, some capacitor became charged up, and it's stored charge,
caused the LED to light.

With all due respect - does the phrase "danger to yourself and others" have any meaning. As described:

a) This thing blows a 25A fuse on contact. Even instant fuses will handle an overload for some period of time which is a function of load and duration.. So in instant failure = Dead Short.

b) Sure, an LED taking a micro-current might light from residual current stored somewhere along the current path. But that does not suggest that the system is functioning properly.

c) Who knows what part of the system is being switched. It is *VERY* unlikely that the actual switch you are using is handling either the 25A input at 12V or the 400-700-watt output, but rather some relay that is capable of handling the current.

It is very likely that what you have is toast.

http://www.electroschematics.com/wp-...c-inverter.jpg is a very basic schematic for a very low output device - but the principles are the same. You can see multiple opportunities for a short.

Cutting to the chase - either you have a mechanical problem with some part shorting to the case. Or you have a component failure that will require replacement. With your well-proven skills, it is unlikely that you will be able to diagnose the failed part correctly, or if you find *A* bad part, you will not be able to discern whether it is the primary cause or a secondary cause. In any case, given the cost of a NEW inverter of sufficient capacity to manage your load(s) and not either drain your battery or melt it down - get a new inverter. And, design the proper connectors to use it safely. I have seen installations with hard-wired inverters installed with the proper switches. No overheating, no stray wires, no fires. You might consider that option. Get it done by a professional, however.

Peter Wieck
Melrose Park, PA

"using an iron transformer to produce 120V AC output. "

What other kind is there ? /something like stacked Dickson converters ? Or have they found a way to go SMPS with it ?

On Tue, 17 Oct 2017 05:45:40 -0700 (PDT), "
wrote:

With all due respect - does the phrase "danger to yourself and others" have
any meaning. As described:


No danger was involved. It was laying on the lawn outside, I connected
the jumper cables to my farm tractor battery and made sure to tap the
jumper cable to the voltage, not just clamp it on. After the initial
sparks, it attempted to operate.

I since tore it apart, and found the main 12V POS wire was crammed
between the board and the case, and it's insulation was seriously
crushed between the case and the board. But the case is plastic so I
cant see how it would short to that. Anyhow, I taped the wire up, moved
it, and turned the inverter on. For the first 5 minutes it worked fine,
with no load on the output. I then connected a small 120v fan to it, and
the fan worked fine. However, when I unplugged the fan from the
inverter, the inverter red light began flashing and the buzzer began
beeping, and it no longer produced any AC output voltage. Even after
disconnecting it from the 12V battery and letting it sit for 24 hours,
it still just flashes the red light and beeps.

I have given up trying to repair it, and bought a new inverter. Because
it has SMD devices inside, I wont even try to repair it at this point.
It's now in my junk box, intended only to be used for parts. The case
will come in handy for some project, it's small internal fan may be
used, along with the switch and a few other parts. The circuit board
will likely just go in the garbage, because who knows what parts are
fried on it. But for now, I didn't feel like ripping it apart again, so
the whole thing went in my scrap box.

I have read several websites that say this is a common problem with this
model, and it's not highly rated. Cobra has been known to produce
quality CB radios, but apparently this inverter is has a lot of
problems. I wasted enough time on it. Now it's parts ONLY.

On 10/17/2017 2:54 PM, wrote:
On Tue, 17 Oct 2017 05:45:40 -0700 (PDT), "
wrote:

With all due respect - does the phrase "danger to yourself and others" have
any meaning. As described:


No danger was involved.

Famous last words, "I know what I'm doing."

I wasted enough time on it.

And ours.


--
Jeff-1.0
wa6fwi
http://www.foxsmercantile.com

Foxs Mercantile wrote on 10/17/2017 4:26 PM:
On 10/17/2017 2:54 PM, wrote:
On Tue, 17 Oct 2017 05:45:40 -0700 (PDT), "
wrote:

With all due respect - does the phrase "danger to yourself and others" have
any meaning. As described:


No danger was involved.

Famous last words, "I know what I'm doing."

I wasted enough time on it.

And ours.

He couldn't help himself. You were volunteer labor.

--

Rick C

Viewed the eclipse at Wintercrest Farms,
on the centerline of totality since 1998

On 10/17/2017 11:12 AM, wrote:
"using an iron transformer to produce 120V AC output."

What other kind is there ? /something like stacked Dickson converters ? Or have they found a way to go SMPS with it ?


Imagine like a Class D audio power amp type topology that can put out a
120VAC 60Hz sine wave.

wrote:

"using an iron transformer to produce 120V AC output. "

What other kind is there ?


** The most common is a full bridge, mosfet output stage producing a "modified square wave" output.

More expensive units use a similar stage running is a class D to produce a good sine wave.

In both cases, the 12VDC input is stepped up to 170V ( or 340V ) DC to power the output stage.


..... Phil