Motor thermal protection without temperature sensor
This function is to realize the motor thermal protection based on the thermal
model of motor.
Code
Name
Setting range
Default
Min.
Attri.
C1.69 Motor thermal model protection setting
0: Inactive
1: Active
0
–
Stop
C1.74 Motor thermal model protection time con-
stant
0.0...400.0 min
DOM
0.1
Stop
[C1.74] is obtained by the equation below:
Cv:
Specific heat capacity
(J/kg)
Cv of iron (Fe):
450 J/kg
Cv of aluminum (Al): 900 J/kg
M:
Motor weight (kg)
Fig. 12-47: Motor thermal model protection time constant
Increase the value of [C1.74] 'Motor thermal model protection time constant' ap-
propriately if motor overload protection error code 'OL-2' occurs frequently. This
function can be disabled by setting [C1.69] = 0, if necessary.
Ensure that the converter output current does not exceed 110 % of the [C1.07]
'Motor rated current'.
Motor overload pre-warning
Code
Name
Setting range
Default
Min.
Attri.
C1.70 Motor overload pre-warning level
100.0...250.0 %
100.0
0.1
Run
C1.71 Motor overload pre-warning delay 0.0...20.0
2.0
0.1
Run
E2.15 Relay 1 output selection
12: Motor overload pre-
warning
1
–
Stop
When the output current exceeds the threshold defined by C1.70 'Motor over-
load pre-warning level' for [C1.71] 'Motor overload pre-warning delay', the pre-
warning signal is active on DO1 or Relay 1 output. Users may use the indication
of this pre-warning signal according to actual application situations. The signal is
immediately deactivated when the output current is lower than the threshold.
Bosch Rexroth AG
Functions and Parameters
VFC 3210
158/253
DOK-RCON04-VFC3210****-IT01-EN-P