Thermal Model - GE 469 Instruction Manual

5.6.2

Thermal Model

 THERMAL
MODEL
5–40

PATH: SETTINGS S5 THERMAL MODEL
[] SELECT CURVE STYLE:
Standard
OVERLOAD PICKUP
MESSAGE
LEVEL: 1.01 x FLA
ASSIGN TRIP RELAYS:
MESSAGE
Trip
UNBALANCE BIAS
MESSAGE
K FACTOR: 0
COOL TIME CONSTANT
MESSAGE
RUNNING: 15 min.
COOL TIME CONSTANT
MESSAGE
STOPPED: 30 min.
HOT/COLD SAFE
MESSAGE
STALL RATIO: 1.00
ENABLE RTD
MESSAGE
BIASING: No
RTD BIAS
MESSAGE
MINIMUM: 40°C
RTD BIAS CENTER
MESSAGE
POINT: 130°C
RTD BIAS
MESSAGE
MAXIMUM: 155°C
THERMAL CAPACITY
MESSAGE
ALARM: Off
ASSIGN ALARM RELAYS:
MESSAGE
Alarm
THERMAL CAP. ALARM
MESSAGE
LEVEL: 75% USED
THERMAL CAPACITY
MESSAGE
ALARM EVENTS: Off
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
Range: Standard, Custom, Voltage
Range: 1.01 to 1.25 in steps of 0.01
Range: Trip, Trip & Aux2, Trip & Aux2 &
Range: 0 to 19 in steps of 1. (0 defeats
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
Range:
Range:
Range: Off, Latched, Unlatched
Range: Alarm, Alarm & Auxiliary2,
Range: 10 to 100% in steps of 1
Range: On, Off

MOTOR THERMAL CAPACITY USED
469 MOTOR MANAGEMENT RELAY – INSTRUCTION MANUAL
CHAPTER 5: SETTINGS
Dependent
Aux3, Trip & Aux3
this feature)
value
RTD BIAS CENTER
in steps of 1
value to
RTD BIAS MINIMUM
value
RTD BIAS MAXMIMUM
in steps of 1
value to
RTD BIAS CENTER
250°C in steps of 1
Alarm & Aux2 & Aux3, Alarm &
Auxiliary3, Auxiliary2, Aux2 &
Aux3, Auxiliary3, None
actual value register.