GE 239 Instruction Manual page 79

CHAPTER 4: PROGRAMMING
239 MOTOR PROTECTION RELAY – INSTRUCTION MANUAL
Courtesy of NationalSwitchgear.com
EXAMPLE 1: PTC THERMISTOR
S4:PROTECTION\TEMPERATURE\THERMISTOR\THERMISTOR HOT RESISTANCE:
Ω
10.0 K
S4:PROTECTION\TEMPERATURE\THERMISTOR\THERMISTOR COLD RESISTANCE:
Ω
0.5 K
S4:PROTECTION\TEMPERATURE\THERMISTOR\THERMISTOR FUNCTION: TRIP
The thermistor trip will occur when the thermistor input resistance is greater than
or equal to the
S4: \PROTECTION\TEMPERATURE\THERMISTOR\THERMISTOR HOT
setting of
RESISTANCE
The thermistor trip can be reset when the thermistor input resistance becomes
less than the
S4:PROTECTION\TEMPERATURE\THERMISTOR\THERMISTOR COLD
RESISTANCE setting of
EXAMPLE 2: NTC THERMISTOR
S4:PROTECTION\TEMPERATURE\THERMISTOR\THERMISTOR HOT RESISTANCE:
Ω
0.7 K
S4:PROTECTION\TEMPERATURE\THERMISTOR\THERMISTOR COLD RESISTANCE:
Ω
12.0 K
S4:PROTECTION\TEMPERATURE\THERMISTOR\THERMISTOR FUNCTION: TRIP
The thermistor trip will occur when the thermistor input resistance is less than or
equal to the
S4:\PROTECTION\TEMPERATURE\THERMISTOR\THERMISTOR HOT
RESISTANCE setting of
The thermistor trip can be reset when the thermistor input resistance becomes
greater than the S4:PROTECTION\TEMPERATURE\THERMISTOR\THERMISTOR
setting of
COLD RESISTANCE
• THERMISTOR NOT CONNECTED ALARM: If the thermistor becomes open circuited
during use, the ACTUAL VALUES display for the thermistor will be "NOT CONNECTED".
The 239 relay will generate an alarm to warn of the fault if this setpoint is enabled.
RTD 1-3 (option)
Protection against excessive motor temperature due to loss of ventilation or high ambient
temperatures is provided by the RTD option which must be ordered with the relay if
required. Up to 3 resistance temperature detectors (RTDs) must be supplied with the motor
to use this option. When ordering a motor with RTDs, the 100 Ω platinum DIN 43730 type is
the preferred choice for optimum sensitivity and linearity. Other RTDs that can be selected
are 100 Ω nickel, 120 Ω nickel and 10 Ω copper.
• RTD 1-3 APPLICATION: RTDs can be located in the stator windings or the bearings.
Specify the location of each RTD in this setpoint. The application name selected here
will be displayed as part of the alarm and trip message. If a particular RTD input is not
used, this setpoint should be set to off.
• RTD 1-3 TYPE: This setpoint must be programmed to the type of RTD for each of the
RTDs connected. The factory default is 100 Ω platinum but 100 Ω nickel, 120 Ω nickel,
or 10 Ω copper can also be connected to each input.
Ω
.
10.0 K
Ω
0.5 K .
Ω
0.7 K .
Ω
.
12.0 K
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