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.