Quote:
Originally Posted by JohnCT
You won't damage your meter no matter what you do. The highest voltages on a plasma are below 400V under any condition.
On the power supply, there are test points marked for the VS and VA, which are developed on that board. There are also other voltages that are generated on the sustain boards, but that's farther down the road.
If there are no test points, then use the large harness connectors. The VS will usually have two to four pins all paralleled for current capability and the VA one or two, but the boards are marked for these voltages right at the connector.
For either voltage, you use cold ground as reference, which would be any of the mounting screws (other than upper and lower buffer board mounting screws which might be above ground) or even the entire back side of the plasma display itself.
Other voltages on the sustain boards can be referenced to cold ground or depending on maker, there might be two test points printed on the board to check those voltages.
But for now, our first attack is to see if the power supply is working, so the VS and VA voltages are the first step.
John
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Hi again John,
I found the measurement process straightforward. Here is what I found.
VS voltage marked on the panel is 208 volts. I measured a high of 463 volts at startup, then it steadily dropped until stabilizing at 23 volts.
VA voltage marked on the panel is 57 volts. I measured a high of 126 volts at startup, dropping to zero after several seconds.
I repeated the measurements a few times...always the same. This, to me, suggests there is a power supply issue.