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Father Haskell Father Haskell is offline
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Default Problem with fluorescent lamp or ballast

On Jul 21, 8:23 am, Yong Huang wrote:
On Jul 20, 8:59 pm, Father Haskell wrote:



On Jul 20, 6:46 pm, Yong Huang wrote:


One pair of the fluorescent lamps in the kitchen stopped working. I
replaced with the other pair in the same big box on the ceiling. They
still didn't work. Then I bought a ballast from Home Depot, a magnetic
type, and installed it. One of the two bulbs can flash with dim light.
I did this before (in a different place). Replacing ballast and all
was well. But this time I'm at a loss.


Can somebody tell me how I check the ballast or circuit? I did all the
following measurements. Both ballasts are like this:


_________
Blk | | Blu
W | | Blu
Y | | R
Y |_________| R


Old ballast:
Blk to W: 12ohm; Y to Y: 2 ohm
Blu to Blu or R to R: 2 ohm; no continuity between Blu and R
Blk to Blu: 3ohm; W to Blu: 10ohm


New ballast:
Blk to W: 8ohm; Y to Y: no continuity
Blu to Blu or R to R or : no continuity
Blk to one Blu: 1.5ohm; Blk to the other Blu: no continuity
W to the first Blu: 8ohm; W to the other Blu: no continuity


After I turned power on, I checked the voltage on the wires when the
new ballast is installed:
Blk: 120v; Y and W: 0
Blu: 120v; one R: 0; the other R: 140v


Of all the 4 sockets (for 2 bulbs), one which 2 blue wires go in has
120V. The other 3 are 0.


I don't know what I should measure exactly. Thanks for help.


Yong Huang


Do the tubes light up when you brush a hand over them?
Check your ground. Tubes must be within 1/2" of a
grounded metal surface (the chassis) or they won't
start.


One of the tubes will show dim flickering light if I rub on it. The
other one still doesn't work.

To Art, I even moved the other known good tubes into these two
sockets. They still don't work. I checked the inside of the sockets. I
didn't see rust or anything. Thanks.

Yong


Wrap a grounded wire around the tube (watch the end so
it doesn't short out a terminal pin). Tube should light up
with no problems.