Dimmer won't work when connected to power inverter

I successfully tested an 18ft long section of rope lights (Hunter brand) and a 3-stage touch dimmer in my house before taking out to install it in my RV. After plugging it into my 12VDC to 110VAC power inverter it just has one brightness level which is maximum brightness. Once its on, I can't turn it off again without unplugging it. I tried using a standard incandescent rotary dimmer with the exact same results. Why is this happening?

Why does it work properly on 110V 60Hz household current but not with the power inverter? Thanks.

"Chuck" wrote in message newsOUPi.148422$Fc.93550@attbi_s21...
Dimmer won't work when connected to power inverter

I successfully tested an 18ft long section of rope lights (Hunter brand) and a 3-stage touch dimmer in my house before taking out to install it in my RV. After plugging it into my 12VDC to 110VAC power inverter it just has one brightness level which is maximum brightness. Once its on, I can't turn it off again without unplugging it. I tried using a standard incandescent rotary dimmer with the exact same results. Why is this happening?

Why does it work properly on 110V 60Hz household current but not with the power inverter? Thanks.
----
The waveform from the inverter may not be appropriate to a device which expects a sinusoidal or near sinusoidal wave. Your inverter which is probably intended for resistive loads (or loads such as a TV in which conversion to a different level or levels of DC takes place) may not provide a true sine wave and possibly even gives a square wave which makes the dimmer simply turn on fully no matter how you set it.

--

Don Kelly
remove the X to answer
----------------------------

Don Kelly wrote:

"Chuck" wrote in message
newsOUPi.148422$Fc.93550@attbi_s21... Dimmer won't work when
connected to power inverter

I successfully tested an 18ft long section of rope lights (Hunter
brand) and a 3-stage touch dimmer in my house before taking out to
install it in my RV. After plugging it into my 12VDC to 110VAC
power inverter it just has one brightness level which is maximum
brightness. Once its on, I can't turn it off again without
unplugging it. I tried using a standard incandescent rotary dimmer
with the exact same results. Why is this happening?

Why does it work properly on 110V 60Hz household current but not
with the power inverter? Thanks. ----
The waveform from the inverter may not be appropriate to a device
which expects a sinusoidal or near sinusoidal wave. Your inverter
which is probably intended for resistive loads (or loads such as a
TV in which conversion to a different level or levels of DC takes
place) may not provide a true sine wave and possibly even gives a
square wave which makes the dimmer simply turn on fully no matter
how you set it.

--

Don Kelly
remove the X to answer
----------------------------

Yes this is the reason. The inverter outputs a square wave. You could
try reducing the 12 volts supply to say 10 and see if the change in
output is enough. But you may have to watch for overheating the
inverter. Another way would be to filter the inverter output but you
will need to have some fairly big chokes to handle the load.

--
Best Regards:
Baron.

Thank you both. I knew it was an issue of this sort but I didn't know what.

Chuck

The waveform from the inverter may not be appropriate to a device
which expects a sinusoidal or near sinusoidal wave. Your inverter
which is probably intended for resistive loads (or loads such as a
TV in which conversion to a different level or levels of DC takes
place) may not provide a true sine wave and possibly even gives a
square wave which makes the dimmer simply turn on fully no matter
how you set it.

--

Don Kelly
remove the X to answer
----------------------------

Yes this is the reason. The inverter outputs a square wave. You could
try reducing the 12 volts supply to say 10 and see if the change in
output is enough. But you may have to watch for overheating the
inverter. Another way would be to filter the inverter output but you
will need to have some fairly big chokes to handle the load.

--
Best Regards:
Baron.

On Sat, 13 Oct 2007 10:00:07 +0100, Baron
wrote:

Don Kelly wrote:

"Chuck" wrote in message
newsOUPi.148422$Fc.93550@attbi_s21... Dimmer won't work when
connected to power inverter

I successfully tested an 18ft long section of rope lights (Hunter
brand) and a 3-stage touch dimmer in my house before taking out to
install it in my RV. After plugging it into my 12VDC to 110VAC
power inverter it just has one brightness level which is maximum
brightness. Once its on, I can't turn it off again without
unplugging it. I tried using a standard incandescent rotary dimmer
with the exact same results. Why is this happening?

Why does it work properly on 110V 60Hz household current but not
with the power inverter? Thanks. ----
The waveform from the inverter may not be appropriate to a device
which expects a sinusoidal or near sinusoidal wave. Your inverter
which is probably intended for resistive loads (or loads such as a
TV in which conversion to a different level or levels of DC takes
place) may not provide a true sine wave and possibly even gives a
square wave which makes the dimmer simply turn on fully no matter
how you set it.

--

Don Kelly
remove the X to answer
----------------------------

Yes this is the reason. The inverter outputs a square wave. You could
try reducing the 12 volts supply to say 10 and see if the change in
output is enough.

---
The change in output amplitude has nothing to do with it.

The reason it's not working is because the fast-rising edge of the
square wave output is defeating the intended purpose of the
phase-control circuitry. He

http://www.littelfuse.com/data/en/Ap...tes/AN1003.pdf


--
JF

On Sat, 13 Oct 2007 01:02:13 GMT, "Chuck" wrote:

Dimmer won't work when connected to power inverter

I successfully tested an 18ft long section of rope lights (Hunter brand) and a 3-stage touch dimmer in my house before taking out to install it in my RV. After plugging it into my 12VDC to 110VAC power inverter it just has one brightness level which is maximum brightness. Once its on, I can't turn it off again without unplugging it. I tried using a standard incandescent rotary dimmer with the exact same results. Why is this happening?

Why does it work properly on 110V 60Hz household current but not with the power inverter? Thanks.

Yep, it won't work with an inverter. Now you know! g

Sine wave for household current, square wave from the inverter. There
is no slope on the square wave to get partial voltage, so no dimming.

There are 'tricks' you can do to make it work somewhat, but I won't
get into them, and they are much too much work to be practical
(basicalyl converting the square wave into a more sine wave form.)

John Fields wrote:

On Sat, 13 Oct 2007 10:00:07 +0100, Baron
wrote:

Don Kelly wrote:

"Chuck" wrote in message
newsOUPi.148422$Fc.93550@attbi_s21... Dimmer won't work when
connected to power inverter

I successfully tested an 18ft long section of rope lights (Hunter
brand) and a 3-stage touch dimmer in my house before taking out to
install it in my RV. After plugging it into my 12VDC to 110VAC
power inverter it just has one brightness level which is maximum
brightness. Once its on, I can't turn it off again without
unplugging it. I tried using a standard incandescent rotary
dimmer
with the exact same results. Why is this happening?

Why does it work properly on 110V 60Hz household current but not
with the power inverter? Thanks. ----
The waveform from the inverter may not be appropriate to a device
which expects a sinusoidal or near sinusoidal wave. Your inverter
which is probably intended for resistive loads (or loads such as a
TV in which conversion to a different level or levels of DC takes
place) may not provide a true sine wave and possibly even gives a
square wave which makes the dimmer simply turn on fully no matter
how you set it.

--

Don Kelly
remove the X to answer
----------------------------

Yes this is the reason. The inverter outputs a square wave. You
could try reducing the 12 volts supply to say 10 and see if the change
in output is enough.

---
The change in output amplitude has nothing to do with it.

The reason it's not working is because the fast-rising edge of the
square wave output is defeating the intended purpose of the
phase-control circuitry. He

http://www.littelfuse.com/data/en/Ap...tes/AN1003.pdf

Hi John.
The reason I suggested changing the input voltage was because
the OP wanted to dim the rope lights.

--
Best Regards:
Baron.

On Sat, 13 Oct 2007 16:41:28 +0100, Baron
wrote:

John Fields wrote:

The change in output amplitude has nothing to do with it.

The reason it's not working is because the fast-rising edge of the
square wave output is defeating the intended purpose of the
phase-control circuitry. He

http://www.littelfuse.com/data/en/Ap...tes/AN1003.pdf

Hi John.
The reason I suggested changing the input voltage was because
the OP wanted to dim the rope lights.

---
Hmm... I didn't even think of that, Thanks! :-)


--
JF

On 13 Oct, 02:02, "Chuck" wrote:
Dimmer won't work when connected to power inverter

I successfully tested an 18ft long section of rope lights (Hunter brand) and a 3-stage touch dimmer in my house before taking out to install it in my RV. After plugging it into my 12VDC to 110VAC power inverter it just has one brightness level which is maximum brightness. Once its on, I can't turn it off again without unplugging it. I tried using a standard incandescent rotary dimmer with the exact same results. Why is this happening?

Why does it work properly on 110V 60Hz household current but not with the power inverter? Thanks.

You could maybe fiddle with the inverter to try to sine up the
waveform.
A capacitor across the transformer would help.
The value is down to trial and error.

What about rectifying the 110V AC and using a DC/PWM dimmer?
"Chuck" wrote in message newsOUPi.148422$Fc.93550@attbi_s21...
Dimmer won't work when connected to power inverter

I successfully tested an 18ft long section of rope lights (Hunter brand) and a 3-stage touch dimmer in my house before taking out to install it in my RV. After plugging it into my 12VDC to 110VAC power inverter it just has one brightness level which is maximum brightness. Once its on, I can't turn it off again without unplugging it. I tried using a standard incandescent rotary dimmer with the exact same results. Why is this happening?

Why does it work properly on 110V 60Hz household current but not with the power inverter? Thanks.

was: Dimmer won't work when connected to power inverter

Farticus wrote:
Why does it work properly on 110V 60Hz household current
but not with the power inverter?

**** off, you lazy *******.

"JeffM" wrote in message
oups.com...
was: Dimmer won't work when connected to power inverter

Farticus wrote:
Why does it work properly on 110V 60Hz household current
but not with the power inverter?

**** off, you lazy *******.


Thank you Jeff, you are so kind and good hearted.
What a lovely person you must be.