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hr(bob) [email protected] hr(bob) hofmann@att.net is offline
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Default Determine voltage of a Christmas tree minibulb?

On Dec 22, 3:02*pm, "James Sweet" wrote:
"Bill Jeffrey" wrote in message

...





Chuck wrote:


Just count the number of bulbs that go out when you remove a bulb from a
working string...
then divide * 120 volts (if in North America) by the number of bulbs in
each section,


10 bulbs would be 12 volt bulbs
20 bulbs would be 6 volt bulbs
50 *bulbs or so would be 2.5 volt bulbs
These are nominal voltages, *Some strings use a few more bulbs and run
not as bright.


Now that was a good common-sense troubleshooting response. *Right to the
point. *Excellent!


Good answer, but that wasn't his question. If I read the OP correctly, he
has a bulb in his hand (not in a string) and doesn't know which string it
goes into. In other words, he doesn't know how many volts it takes to
light this particular bulb.


Just put it in a string and see what it does. Most are either 2.5 or 3.5V,
with older ones being 6V. Even if you put a 2.5V bulb in a 6V string, it
will not usually blow instantly, you can tell if the brightness is way off
if it's wrong.- Hide quoted text -

- Show quoted text -


That's why I suggested starting out with the string of lamps/bulbs
plugged into a lamp dimmer switch, like you would use on any
incandescent light. I have burned out a few bulbs trying your method,
when pluged into a full 120V circuit.

Bob H