Just installed a replacement dimmer switch that exhibits the same
strange behavior as the previous one.

It's on a circuit that's wired correctly. I have a dedicated outlet
running a string of low-voltage halogen lights through a transformer.
When I installed the first dimmer, it worked fine. When I checked it
with my handy-dandy circuit checker (you know, the type with the 3
leds), it indicated the circuit was OK with the power applied. BUT: when
the dimmer was switched off, the tester indicated a fault ("open
neutral", it said).

So I replaced the dimmer temporarily with a single-pole switch; circuit
acted normally with power on and off.

Then I replaced the dimmer (it's a Lutron "decora"-style with the big
rocker switch on front and a little slider doohickey). Guess what? Same
deal; tester says "OK" when on but "open neutral" when off.

What gives? All I can think is that the dimmer is drawing just enough
current when in the "off" position to spook the tester. (Yeah, I know
those types of testers aren't 100% conclusive, but shoot, it's better
than sticking your fingers on the damn wires.) Why this would be the
case, I have no idea.

Although, I just realized: the dimmer packaging says "locator light" on
it; is there a dim light on this that is drawing this current? (I'm not
at my client's site right now.)

D "puzzled" N


--
Just as McDonald's is where you go when you're hungry but don't really
care about the quality of your food, Wikipedia is where you go when
you're curious but don't really care about the quality of your knowledge.

- Matthew White's WikiWatch (http://users.erols.com/mwhite28/wikiwoo.htm)

"David Nebenzahl" wrote in message
s.com...
What gives? All I can think is that the dimmer is drawing just enough
current when in the "off" position to spook the tester. (Yeah, I know
those types of testers aren't 100% conclusive, but shoot, it's better than
sticking your fingers on the damn wires.) Why this would be the case, I
have no idea.

Although, I just realized: the dimmer packaging says "locator light" on
it; is there a dim light on this that is drawing this current? (I'm not at
my client's site right now.)

Some of these devices allow a trickle of current to flow through the bulb so
they can keep the circuitry energized. X10 switches work this way.

Steve spake thus:

"David Nebenzahl" wrote in message
s.com...

What gives? All I can think is that the dimmer is drawing just enough
current when in the "off" position to spook the tester. (Yeah, I know
those types of testers aren't 100% conclusive, but shoot, it's better than
sticking your fingers on the damn wires.) Why this would be the case, I
have no idea.

Although, I just realized: the dimmer packaging says "locator light" on
it; is there a dim light on this that is drawing this current? (I'm not at
my client's site right now.)

Some of these devices allow a trickle of current to flow through the bulb so
they can keep the circuitry energized. X10 switches work this way.

But why keep the circuit energized? (This isn't an X10 device.)


--
Just as McDonald's is where you go when you're hungry but don't really
care about the quality of your food, Wikipedia is where you go when
you're curious but don't really care about the quality of your knowledge.

- Matthew White's WikiWatch (http://users.erols.com/mwhite28/wikiwoo.htm)

David, I answered your question about Color Return in
sci.electronics.repair.

"David Nebenzahl" wrote in message
s.com...
Just installed a replacement dimmer switch that exhibits the same
strange behavior as the previous one.

It's on a circuit that's wired correctly. I have a dedicated outlet
running a string of low-voltage halogen lights through a transformer.
When I installed the first dimmer, it worked fine. When I checked it
with my handy-dandy circuit checker (you know, the type with the 3
leds), it indicated the circuit was OK with the power applied. BUT: when
the dimmer was switched off, the tester indicated a fault ("open
neutral", it said).

So I replaced the dimmer temporarily with a single-pole switch; circuit
acted normally with power on and off.

Then I replaced the dimmer (it's a Lutron "decora"-style with the big
rocker switch on front and a little slider doohickey). Guess what? Same
deal; tester says "OK" when on but "open neutral" when off.

What gives? All I can think is that the dimmer is drawing just enough
current when in the "off" position to spook the tester. (Yeah, I know
those types of testers aren't 100% conclusive, but shoot, it's better
than sticking your fingers on the damn wires.) Why this would be the
case, I have no idea.

Although, I just realized: the dimmer packaging says "locator light" on
it; is there a dim light on this that is drawing this current? (I'm not
at my client's site right now.)

D "puzzled" N


--
Just as McDonald's is where you go when you're hungry but don't really
care about the quality of your food, Wikipedia is where you go when
you're curious but don't really care about the quality of your knowledge.

- Matthew White's WikiWatch (http://users.erols.com/mwhite28/wikiwoo.htm)


Forget about your tester. What is the problem with the lights? Are they
flickering? Is the transformer making noise? For a transformer load it is
usually a good idea to use a dimmer rated for a magnetic load unless the
transformer is electronic in which case use a dimmer rated for an electronic
load. A locator switch has a small pilot light that is on when the switch is
off so that you can locate the switch in the dark.

David Nebenzahl wrote:


Then I replaced the dimmer (it's a Lutron "decora"-style with the big
rocker switch on front and a little slider doohickey). Guess what? Same
deal; tester says "OK" when on but "open neutral" when off.



Although, I just realized: the dimmer packaging says "locator light" on
it; is there a dim light on this that is drawing this current? (I'm not
at my client's site right now.)


I put a similar "decora"-style dimmer switch in my bathroom about a
month ago, which has a neon locator light. On my switch, there was a
small slider switch you can use to enable or disable the locator lamp,
it's covered by the cover plate when you put the cover back on the
switch. Have you tried switching off the locator lamp to see if that
makes a difference?

Jerry

spake thus:

David Nebenzahl wrote:

Then I replaced the dimmer (it's a Lutron "decora"-style with the big
rocker switch on front and a little slider doohickey). Guess what? Same
deal; tester says "OK" when on but "open neutral" when off.

Although, I just realized: the dimmer packaging says "locator light" on
it; is there a dim light on this that is drawing this current? (I'm not
at my client's site right now.)

I put a similar "decora"-style dimmer switch in my bathroom about a
month ago, which has a neon locator light. On my switch, there was a
small slider switch you can use to enable or disable the locator lamp,
it's covered by the cover plate when you put the cover back on the
switch. Have you tried switching off the locator lamp to see if that
makes a difference?

Now that I don't know; next time I go by my client's place I'll look at it.

Thanks for the only useful response in this thread so far.


--
Just as McDonald's is where you go when you're hungry but don't really
care about the quality of your food, Wikipedia is where you go when
you're curious but don't really care about the quality of your knowledge.

- Matthew White's WikiWatch (http://users.erols.com/mwhite28/wikiwoo.htm)