GE M60 Instruction Manual page 402

GROUPED ELEMENTS
5
The thermal model is the primary protective function of the relay. It consists of the following five key functions:
• Thermal model curve (overload)
• Overload pickup level
• Unbalance biasing of the motor current while the motor is running
• Motor cooling time constants
• Biasing of the thermal model based on hot/cold information and/or measured stator temperature
The algorithm integrates both stator and rotor heating into a single model. The motor heating level is maintained in the
thermal capacity used register. When the motor has been stopped for a long time, it is at ambient temperature and
thermal capacity used is zero. When the motor is in overload, the output operand is set once the thermal capacity used
reaches 100%.
5-194
HOT/COLD SAFE

STALL RATIO: 1.00
RTD BIAS:

Disabled
RTD BIAS MINIMUM

40 C
RTD BIAS CENTER

POINT: 130 C
RTD BIAS MAXIMUM:

155 C
START INHIBIT

TCU MARGIN: 0%
VOLTAGE DEPENDENT

FUNCTION: Disabled
VOLTAGE DEPENDENT

MIN MOTOR VOLTS: 80%
VD VOLTAGE LOSS:

Off
VD STALL CURRENT @

MIN V: 4.50 x FLA
VD SAFE STALL TIME @

MIN V: 20.0 sec.
VD ACCELL. INTERSECT

@ MIN V: 4.00 x FLA
VD STALL CURRENT @

100% V: 6.00 x FLA
VD SAFE STALL TIME @

100% V: 10.0 sec.
VD ACCELL. INTERSECT

@100% V: 5.00 x FLA
THERMAL MODEL

BLOCK: Off
THERMAL MODEL

TARGETS: Self-Reset
THERMAL MODEL

EVENTS: Disabled
Range: 0.01 to 1.00 in steps of 0.01
Range: Disabled, Enabled
Range: 0 to 250°C in steps of 1
Range: 0 to 250°C in steps of 1
Range: 0 to 250°C in steps of 1
Range: 0 to 25% in steps of 1
Range: Disabled, Enabled
Range: 60 to 99% in steps of 1
Range: FlexLogic operand
Range: 1.50 to 20.00 x FLA in steps of 0.01
Range: 0.1 to 1000.0 s in steps of 0.1
Range: 1.50 to 20.00 x FLA in steps of 0.01
Range: 1.50 to 20.00 x FLA in steps of 0.01
Range: 0.1 to 1000.0 s in steps of 0.1
Range: 1.50 to 20.00 x FLA in steps of 0.01
Range: FlexLogic operand
Range: Self-reset, Latched, Disabled
Range: Disabled, Enabled
M60 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 5: SETTINGS