Thermal Model - GE 469 Instruction Manual

5.6.2

Thermal Model

THERMAL
5–38
PATH: SETTINGS S5 THERMAL MODEL
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The primary protective function of the 469 is the thermal model. It consists of five key
elements: the overload curve and overload pickup level, the unbalance biasing of the
motor current while the motor is running, the motor cooling time constants, and the
biasing of the thermal model based on Hot/Cold motor information and measured stator
temperature. Each of these elements are described in detail in the sections that follow.
The 469 integrates stator and rotor heating into one model. Motor heating is reflected in
the
A1 STATUS MOTOR STATUS
If the motor has been stopped for a long period of time, it will be at ambient temperature
THERMAL MODEL
SELECT CURVE
STYLE:
OVERLOAD PICKUP
LEVEL: 1.01 x FLA
ASSIGN TRIP
RELAYS:
UNBALANCE BIAS
K FACTOR: 0
COOL TIME CON-
STANT
COOL TIME CON-
STANT
HOT/COLD SAFE
STALL RATIO: 1.00
ENABLE RTD
BIASING: No
RTD BIAS
MINIMUM: 40°C
RTD BIAS CENTER
POINT: 130°C
RTD BIAS
MAXIMUM: 155°C
THERMAL CAPACITY
ALARM: Off
ASSIGN ALARM
RELAYS:
THERMAL CAP.
ALARM
THERMAL CAPACITY
ALARM EVENTS: Off
MOTOR THERMAL CAPACITY USED
469 MOTOR MANAGEMENT RELAY – INSTRUCTION MANUAL
CHAPTER 5: SETTINGS
Range: Standard, Custom, Voltage
Dependent
Range: 1.01 to 1.25 in steps of 0.01
Range: Trip, Trip & Aux2, Trip & Aux2 &
Aux3, Trip & Aux3
Range: 0 to 19 in steps of 1. (0 defeats
this feature)
Range: 1 to 1000 min. in steps of 1
Range: 1 to 1000 min. in steps of 1
Range: 0.01 to 1.00 in steps of 0.01
Range: Yes, No
Range: 0°C to
RTD BIAS CENTER
in steps of 1
Range: value to
RTD BIAS MINIMUM
RTD BIAS MAXMIMUM
in steps of 1
Range: value to
RTD BIAS CENTER
250°C in steps of 1
Range: Off, Latched, Unlatched
Range: Alarm, Alarm & Auxiliary2,
Alarm & Aux2 & Aux3, Alarm &
Auxiliary3, Auxiliary2, Aux2 &
Aux3, Auxiliary3
Range: 10 to 100% in steps of 1
Range: On, Off
actual value register.
value
value