The value of
Alarm thermal value is set to a level which allows the use of the full
thermal capacity of the motor without causing a trip due to a long overload time.
Generally, the prior alarm level is set to a value of 80 to 90 percent of the trip level.
4.1.10.7
Signals
MPTTR Input signals
Table 478: MPTTR Input signals
Name
Type
Default
Description
I3P
SIGNAL
-
Three-phase currents
BLOCK
BOOLEAN
0=False
Block signal for acti-
vating the blocking
mode
START_EMERG
BOOLEAN
0=False
Signal for indicating
the need for emer-
gency start
AMB_TEMP
FLOAT32
0
The ambient temper-
ature used in the cal-
culation
MPTTR Output signals
Table 479: MPTTR Output signals
Name
Type
Description
OPERATE
BOOLEAN
Operate
ALARM
BOOLEAN
Thermal Alarm
BLK_RESTART
BOOLEAN
Thermal overload indicator,
to inhibit restart
TEMP_RL
FLOAT32
The calculated temperature
of the protected object rela-
tive to the operate level
4.1.10.8
MPTTR Settings
Table 480: MPTTR Group settings (Basic)
Parameter
Values (Range)
Unit
Step
Default
Description
Overload factor
1.00...1.20
0.01
1.05
Overload factor (k)
Alarm thermal value 50.0...100.0
%
0.1
95.0
Thermal level above
which function
gives an alarm
Restart thermal Val 20.0...80.0
%
0.1
40.0
Thermal level above
which function in-
hibits motor re-
starting
Table continues on the next page
1MRS759142 F
Protection functions
REX640
Technical Manual
421