GE SPM Series, Instruction Manual

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GE Power Management SPM Synchronous Motor Protection & Control 7-
3
7 TESTING AND TROUBLESHOOTING 7.2 DISPLAY AND MESSAGES
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7.2 DISPLAY AND MESSAGES 7.2.1 DISPLAY
The PQM uses the alphanumeric display to indicate the following information:
• programming prompts
• SPM trip explanations
• readout of the desired motor running parameters
The motor running parameters are displayed as follows.
• Before start, the SPM displays SPM READY .
• While starting, the power factor and line amperes are displayed.
• When the field contactor closes, the SPM momentarily displays FIELD IS APPLIED followed by the normal
running display of line current, field current (if this option is furnished), and motor power factor. The “+” indi-
cates leading power factor (motor generating reactive power) while "–" indicates lagging power factor
(motor consuming reactive power). The unity (1.0) power factor display may have a "+" or "–" sign indicat-
ing that power factor is just slightly leading or lagging.
• Once the motor has synchronized, the SPM displays power factor, line current, field volts (if optioned), field
current (if optioned), and field ohms (if optioned).
7.2.2 SPM MESSAGES
The SPM has a number of built-in messages that may appear during normal operation or if an error is
detected. Errors may occur because the CPU detects a problem internal to the SPM. These messages are
explained in detail below.
• FIELD IS APPLIED : This message appears when the SPM has closed the field contactor. It is displayed
briefly and is a normal SPM function.
• PWR FACTOR TRIP : The motor has been operating below the power factor setpoint too long causing a trip.
• CHECK EXCITER : The field voltage is below the minimum entered in the field undervoltage setpoint. The
exciter should be checked to determine that it is functioning properly. Also, the setpoint should be exam-
ined to see if it is set too high for the normal exciter output.
• FIELD LOSS TRIP! : The field current is less than the field current setpoint. The exciter should be checked for
proper output and the field current setpoint should be checked.
• MISSING VOLTAGE! : The SPM is NOT receiving a power factor reference voltage input to terminals V
1EXT
and V
2EXT
and PF REF is set to External .
• SQL CAGE TRIP! : The SPM has tripped the motor off-line due to a squirrel cage protection trip. The motor
must be allowed to cool for the amount of time displayed by the SPM.
• PULL-OUT TRIP! : A trip has been caused by motor line current exceeding 4 times the full load current set-
point for longer than the PF delay time.
• INCOM SEQ TRIP! : The SPM has tripped the motor due to an incomplete sequence fault. The source of the
fault should be located before the motor is restarted.
• PULL-OUT TRIP! : The SPM has tripped the motor due to pull-out.
• FIELD OVERTEMP! : The SPM has tripped the motor due to overtemperature on the field windings.
• FAIL TO RESYNC! : The SPM has tripped the motor due to a failure to resynchronize.
• START INHIBITED! Ready in xxx min. : The SPM has tripped the motor and will not allow a restart attempt for
xxx minutes.