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269Plus Motor Management Relay GE Power Management
FEATURES 1 INTRODUCTION
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An important feature of the GE Power Management 269Plus Motor Management Relay is its ability to “learn”
individual motor parameters. The relay actually adapts itself to each application by “learning” the values for
motor inrush current, negative sequence current K factor, cool-down rates, and acceleration time. These val-
ues may be used to improve the protective capabilities of the 269Plus (when enabled) and are continually
updated.
The 269Plus calculates the ratio of positive to negative sequence currents. The equivalent motor heating cur-
rent is calculated based upon the “learned” K factor. This, combined with RTD temperature readings by a
motor thermal modeling algorithm, gives the 269Plus a complete thermal model of the motor being protected.
Thus, the 269Plus will allow maximum motor power output while providing complete thermal protection.
The 269Plus relay also provides a complete statistical record of the motor being protected. The total motor run-
ning hours, total MegaWattHours, total motor starts, and the total number of relay trips since the last commis-
sioning are stored and can be viewed on the display. As well, the number of short circuit, RTD, ground fault,
unbalance, overload, start, rapid trips, and undercurrent trips can be recalled by simple keypad commands.
These values are stored along with all of the relay setpoints in non-volatile memory. Thus, even when control
power is removed from the relay, the statistical record, all relay setpoints, learned parameters, and pre-trip val-
ues will remain intact.
The 269Plus can provide one of various output signals for remote metering or programmable controller attach-
ment. Analog signals of motor current as a percentage of full load, hottest stator RTD temperature, percentage
of phase CT secondary current, motor thermal capacity, or bearing temperature are available by field program-
ming. An RS485 port allows access to all setpoints and actual values. A total of four output relays are provided,
including a latched trip relay, an alarm relay, and two auxiliary relays. All output relays may be programmed via
the keypad to trip on specific types of faults or alarms.
When an output relay becomes active, the 269Plus will display the cause of the trip, and if applicable, the lock-
out time remaining. Pre-trip values of average and individual line motor current, unbalance, ground fault cur-
rent, and maximum stator RTD temperature are stored by the 269Plus and may be recalled using the keypad.
The correct operation of the 269Plus relay is continually checked by a built-in firmware self-test routine. If any
part of the relay malfunctions under this self-test, an alarm indication will tell the operator that service is
required.
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