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Using Sensors to Trouble Shoot
KVAL 990-F4 Service Manual
4-22
Using Sensors to Trouble Shoot
• Photo Sensors often get dirty. Make sure they are clean. If they are not clean, debris
may block the signal or provide a false signal.
• Check output voltages of the sensors in the
active
mode. The voltage should effec
-
tively equal
0 VDC
• Check the output voltages of the sensors in
inactive
mode.The voltage should effec
-
tively equal
24 VDC