GE M60 Instruction Manual page 355

CHAPTER 5: SETTINGS
For example, a circuit breaker 52b auxiliary contact is closed when the breaker is open and open when the breaker is
closed. Therefore the setting is "Cont Ip n On." For a 52a contact, the setting is "Cont Ip n Off."
Four mutually exclusive FlexLogic operands that reflect the motor state are generated by a state machine in the relay to
determine motor status. They are
The state machine initially sets the
and motor current is less than 2% of FLA. If the previous motor status is offline, a phase current greater than 2% of FLA is
detected, and the
MOTOR OFFLINE
motor current is less than FLA times the
for the use of a soft-starter mechanism that slowly increases current such that it never exceeds FLA × overload factor
during a starting sequence). For normal starting, the
× overload factor, at which time the
the operand is set. If current then falls below FLA × overload factor, the
MOTOR OVERLOAD
and the operand is set. A
MOTOR RUNNING
When two-speed motor functionality is employed, this setting is used to indicate the breaker or contactor position at
speed 1. As such, the speed 1 auxiliary contact is connected to the input specified by this setting for two-speed
applications.
— As the name implies, this feature i s only used in an emergency, as it defeats the purpose of the
EMERGENCY RESTART
relay—protecting the motor. The input selected by this setting is used to reset the motor thermal capacity used from its
current value to 0% so that a hot motor can be restarted. However, trip conditions that are still present (for example, hot
RTD) still cause a trip. In the event of a real emergency, the
emergency is over. Any
EMERGENCY RESTART
— This setting selects the source connected to phase current transformers on the power system side
MOTOR LINE SOURCE
of the stator winding.
— This setting selects number of motor start and stop records to average data presented in
NUMBER OF STARTS TO LEARN
the
ACTUAL VALUES  RECORDS  MOTOR LEARNED DATA
MOTOR LOAD AVERAGE CALC. PERIOD
calculated. The calculation is a sliding window.
— This setting enables/disables the two-speed motor function. This function provides proper
2-SPEED MOTOR PROTECTION
protection for a two-speed motor where there are two different full load values. The two-speed functionality is required for
motors having two windings wound into one stator. One winding, when energized, provides one of the speeds. When the
second winding is energized, the motor takes on the speed determined by the second winding. The M60 algorithm
integrates the heating at each speed into one thermal model using a common thermal capacity used register value for
both speeds. Using the M60 for such applications provides several options, allowing the removal of traditional wiring and
interlocking:
• Use the M60 front panel pushbuttons and provide necessary operate and interlock logic via FlexLogic
• Use external pushbuttons and provide necessary operate and interlock logic using FlexLogic shown as follows
• Use a traditional external control schematic with some connections to the M60 for control and protection
— If the two-speed motor feature is used, this setting specifies a FlexLogic operand to indicate the
SPEED2 MOTOR SWITCH
current motor speed. This is typically an indication that the contactor at speed 2 is energized. When the assigned FlexLogic
operand (typically a contact input operand) is asserted, the algorithm switches to speed 2 (high speed). If the assigned
FlexLogic operand is de-asserted, the algorithm switches to speed 1 (low speed). This allows the M60 to determine which
settings are to be active at any given time. To maintain correct motor status indication, the M60 expects a transition from
speed 1 to speed 2 within two seconds; otherwise, the motor status value can be reset.
— This setting specifies the time delay to transfer from high to low speed. This allows the motor to
SPEED2 SWITCH 2-1 DELAY
slow down before energizing at low speed.
— This setting selects source for a motor protection when two-speed motor functionality is used.
SPEED2 MOTOR SOURCE
This can be separate voltage and current banks or one voltage and current bank one with different full load current value
at the second speed (entered in the
are required for speed 2, then order the relay with two CT banks.
— This setting specifies the motor full load current for speed 2.
SPEED2 MOTOR FLA
M60 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL
MOTOR OFFLINE, MOTOR STARTING,
operand, as the auxiliary contact reports the switching device is open
MOTOR OFFLINE
operand de-asserts, then the
MOTOR OVERLOAD FACTOR
MOTOR STARTING
operand is set. If current rises above FLA × Service Factor at that point,
MOTOR RUNNING
state is determined per the logic noted.
MOTOR OFFLINE
EMERGENCY RESTART
operand transition is logged as an event.
menu.
— This setting specifies the period of time over which parameter averages are
setting). If separate CTs with different ratios or secondary currents
SPEED2 MOTOR FLA
RUNNING, and
MOTOR MOTOR
operand becomes true. After one second, if
MOTOR STARTING
setting, the
MOTOR RUNNING
operand remains set until the current falls below FLA
MOTOR OVERLOAD
operand should remain at logic 1 until the
SYSTEM SETUP
OVERLOAD.
operand is set (this accounts
operand is reset
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