Troubleshooting Electrical Problems
4-27
KVAL 990-F4 Service Manual
1.
Check if the Control Transformer button is pulled
out.
4.
Is there 120 VAC between #1 & #2 on the 120 VAC Terminal Strip? If not, check
the fuse on the output side of the Control Transformer. If fuse is good, check power
coming out of Control Transformer.
5.
If no power on the output side, and there is power going into the top of the Control
Transformer, replace the Control Transformer.
6.
If there is power at the Control Transformer, check the wiring of the black and
white wire going from the Control Transformer to the 120 VAC Terminal Strip.
7.
If there is no power between #1 and #2, check the secondary side of the trans
-
former.
a.Check between X1 and X2. If no power is measured it is a bad transformer.
b.If there is power at X1 and X2, check the other side of the fuse. If now
power, replace the fuse.
2.
Is the Disconnect Switch on the main electrical cabinet set to
ON?
Switch
3.
Is there 208, 220, 440, or 575 VAC to the top side (input) of the Control Trans
-
former? If not, check the fuses at the Fuse Block, and the contacts on the Control
Transformer button on the switch panel.
Input
High Vac
Output
120 Vac
Typical Control Transformer
Control Power Light OFF