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Mycroft668 Mycroft668 is offline
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Default Need help with LED lamp transformer

On Dec 3, 3:35*pm, PeterD wrote:
On Fri, 3 Dec 2010 08:01:53 -0800 (PST), Mycroft668





wrote:
On Dec 1, 8:48 am, PeterD wrote:
On Tue, 30 Nov 2010 07:55:30 -0800 (PST), wrote:
... I know there are transformers that do not
produce output unless under load


Now that's funny! Must be describing those new chinese intelegent
transformers, right?


I'm not sure if you are joking. There really are such things and I
found out the embarrassing way.
I was installing a fancy pendant light and there was a problem in the
wiring. Long story short, I checked the transformer and got almost no
output so I was sure it was defective. I called the supplier and he
told me the transformer didn't output current unless under load. I was
sure he was wrong never having heard of such a thing but after finding
and fixing the short which caused the light not to go on, the
transformer worked perfectly. *Always something new to learn just when
I think I have a full grasp of something!


Mycroft


You sure that light fixture wasn't using a switching power supply? A
transformer is a passive device, it doesn't know whether there is a
load or not, it just transforms one voltage to another.


No, I'm not sure. There was a little transformer-like box that went in
the electrical box and the supplier said he gets calls like mine all
the time. (If the directions were better, he wouldn't be bothered so
much but that's another story)

I'm sure you know more than I and sorry if I was wrong. I DO know I
put a tester on one of the transformers I have (output 12VDC 2amp) and
there was a near zero reading, but it worked the light just fine
except for the slight flicker. I ALSO am sure he told me it wouldn't
have an output unless under load. Come to think of it, they are
halogen lights. I don't know why they would need a unit in the
electrical box.

Thanks,
Mycroft