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6.2 POWER ON LED (GREEN) / HEALTH MONITORING RELAY
The Green PWR (Power) LED will be ON when control power is applied to the SIGMA-MD monitor relay and the relay is
operating normally.
The Green PWR (Power) LED will be FLASHING if control power is applied to the SIGMA- MD monitor relay but the
relay is not operating correctly due to a malfunction in the microprocessor circuit. Control power must be turned off
and then restored to reset the SIGMA-MD monitor relay to clear this indication.
The Green PWR (Power) LED will be FLASHING during a manual reset or power on reset as described above.
The health monitoring relay is a solid state DC relay. The relay is on (closed contacts) when the POWER LED is
on and the microprocessor is operating correctly. It de-energizes (opens) if the relay loses control power or if the
microprocessor malfunctions.
6.3 GROUND FAULT LED (RED)
The Red GND FAULT LED will be OFF when the SIGMA-MD monitor relay is operating normally and no ground fault
has been detected and qualified.
The Red GND FAULT LED will be ON when the SIGMA-MD monitor relay has detected and qualified a ground fault.
The RED GND FAULT LED will remain ON until the SIGMA- MD monitor relay is manually reset even if the NGR fault
condition has been corrected (no auto-reset).
The Red GND FAULT LED will be FLASHING when the SIGMA-MD monitor relay is powered up after having
been powered down while indicating a ground fault. The SIGMA- MD monitor relay must be manually reset to
clear this condition.
The Red GND FAULT LED will be ON during a manual reset as described above.
6.4 NGR FAULT LED (RED)
The Red NGR FAULT LED will be OFF when the SIGMA-MD monitor relay is operating normally and no NGR fault has
been detected and qualified.
The Red NGR FAULT LED will be ON when the SIGMA-MD monitor relay has detected and qualified an NGR fault.
The RED NGR FAULT LED will remain ON until the SIGMA-MD monitor relay is manually reset even if the NGR fault
condition has been corrected (no auto-reset).
The Red NGR FAULT LED will be FLASHING when the relay is powered up after having been powered down while
indicating an NGR Fault. The SIGMA-MD monitor relay must be manually reset to clear this condition.
The Red NGR FAULT LED will be ON during a manual reset as described above.
