0>1P@
W>V@
0
H
W
W
W
②
Torque with short ramp-up time
③
Torque with long ramp-up time
④
Torque of the load
⑤
Acceleration torque = Difference between activation torque and torque of load
⑥
Parameterizable limiting torque
⑦
Parameterizable starting torque
t
1
Parameterizable ramp-up time
t
2
Motor has started up and is in rated operation. The start-up is detected and the bypass contacts
close
t
3
Parameterizable ramp-up time
M
e
Rated torque
Parameters
Parameters
Description
Starting torque
The magnitude of the starting torque determines the switch-on torque of the motor. A lower
starting torque results in a lower switch-on torque and a lower starting current.
Select a starting torque that is high enough to ensure that the motor starts immediately and
smoothly when the start command is issued to the 3RW55 or 3RW55 Failsafe soft starter. The
rated torque of the motor is used as the reference value.
• Factory setting: 10%
• Setting range: 10 ... 100%
• In steps of: 5%
Limiting torque
The limiting torque value specifies the maximum torque to be generated in the motor during
start-up. This value also functions as an adjustable torque limit.
The parameter value should be set to approx. 150% to start the motor. It should be high enough
to ensure that the motor does not falter during start-up. This ensures that enough acceleration
torque is generated throughout the motor run-up phase. The rated torque of the motor is used
as the reference value.
Limiting torque ≥ starting torque
• Factory setting: 150%
• Setting range: 20 ... 200 %
• In steps of: 5%
Functions
8.1 Start-up
SIRIUS 3RW55 and 3RW55 Failsafe Soft Starters
Equipment Manual, 02/2022, A5E35630887002A/RS-AF/006
139