Installation manual

2–16 Hardware installation
The voltage LEDs (marked +8 V, –11 V, +11 V, –21 V, and +21 V) can be green, red, or orange. Green means the
input line voltage is adjusted properly for that output. Red means the input line voltage is too low for that output,
so the rotary line voltage selector switch needs to be lowered. Orange means the input line voltage is too high for
that output, so the rotary line voltage selector switch needs to be increased.
a. If any of the voltage LEDs are red, remove power, select the next lower voltage on the selector switch, and
try again. Remember: do not change the rotary line voltage selector switch with power applied.
b. If any of the LEDs are orange, remove power, select the next higher voltage on the selector switch, and try
again. Remember: do not change the rotary line voltage selector switch with power applied.
7. The “FAN” LED is designed to monitor cooling and output voltage ripple of the unit. Under normal conditions
it should be green.
If the FAN LED turns red, the unit is overheating; this can be caused by a failed fan, a dirty air filter, or restricted
air flow to the unit. The most likely cause is a dirty air filter. Allowing the unit to run prolonged at a high temperature
will shorten its life expectancy.
If the FAN LED turns orange, one or more of the output voltages has excessive ripple. This implies that the filter
capacitors need to be replaced.
8. When green, the “CPU” LED indicates that the central processor is running.
9. The Power/Alarm LED on the front panel should turn green after startup.
Any alarm condition on the rear panel will cause the Power/Alarm LED to show red.
10. The rear panel power switch is also a circuit breaker. If the circuit breaker trips, the power switch will switch itself
to OFF.