1-90 Motor Thermal Protection
Option:
Function:
Using ETR (electronic thermal relay), the
motor temperature is calculated based on
frequency, current, and time. If a thermistor
is not present, Danfoss recommends using
the ETR function. The functionality is the
same for asynchronous motors and PM
motors.
NOTICE
ETR calculation is based on motor data
from parameter group
1-2* Motor
Data
.
[0]
No
protection
Disables temperature monitoring.
[1]
Thermistor
warning
A thermistor issues a warning if the upper
limit of motor temperature range is
exceeded.
[2]
Thermistor
trip
If the upper limit of motor temperature
range is exceeded, a thermistor gives an
alarm and makes the frequency converter
trip.
[3]
ETR warning
1
If the calculated upper limit of the motor
temperature range is exceeded, a warning
occurs.
[4]
ETR trip 1
If 90% of calculated upper limit of motor
temperature range is exceeded, an alarm
occurs and frequency converter trips.
[22] ETR Trip -
Extended
Detection
Start motor thermal calculation based on the
actual load and time as well as the motor
frequency when the motor current is above
110% of the nominal motor current. Alterna-
tively, start motor thermal calculation when
the motor current is less than 110% of the
nominal motor current, and the current limit
is triggered.
Parameters
Programming Guide
MG03N202
Danfoss A/S © 11/2015 All rights reserved.
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