Start Light OFF
If the Start light remains unlit, push in the Start button
and hold it in while a second person checks for volt-
age between #2 and #75. If there is 110 VAC, replace
the ACR relay. If there is no voltage while the button
is held in, check the wiring.
First isolate the power supply. Check between DC+
and DC- for 24VDC. If no DC voltage, disconnect
the output (V+ and V-) wires from the 24VDC
power supply and check for DC voltage where
those wires were disconnected.
If no voltage:
Check the input side for 110 VAC. If no 110 VAC, check the fuse. If there is 110
VAC and no 24VDC, replace the 24VDC Power Supply.
If there is 24VDC:
Reconnect the output wires to the 24VDC power supply.
Trace the output wire to the DC terminal block.
Disconnect all (+ 24V positive) wires from the + DC from the DC terminal block
except the + output wire from the + 24VDC power supply.
Check for +24VDC at between any –DC and +DC terminal on the DC Terminal
block.
Reinstall the (+ 24V positive) wires one by one, checking for +24VDC after
installing each. If at any point no voltage is found trace the last reinstalled wire and
check for shorts.
Input 110 VAC
Output 24 VDC
24VDC Light OFF
Troubleshooting Electrical Problems
6-11
KVAL 990-HB Operation / Service Manual
Summary of Contents for 990-HB
Page 4: ...KVAL 990 HB Operation Manual ...
Page 25: ...Safety Sign Off Sheet 1 17 KVAL 990 HB Operation Service Manual ...
Page 26: ...Safety Sign Off Sheet 1 18 KVAL 990 HB Operation Service Manual ...
Page 66: ...Diagnostic Screen 2 40 KVAL 990 HB Operation Service Manual ...
Page 84: ...Calibration of the Back Section 3 18 KVAL 990 HB Operation Service Manual ...
Page 88: ...System IT Administration 4 4 KVAL 990 HB Operation Service Manual ...