Siemens 3RW44 - 4.2 Design of the Feeder

Installation, connection and feeder configuration
4.2 Design of the feeder
3RW44 soft starters
32 Manual, 03/2017, NEB535219502000/RS-AB/008
4.2
Design of the feeder
4.2.1
General information
WARNING
Automatic restart
Can result in death, serious injury, or property damage.
The automatic reset mode must not be used in applications where there is a risk of serious
injury to persons or substantial damage to property if the motor starts up again
unexpectedly.
The start command (e.g. issued by the PLC) must be reset prior to issuing a reset
command, because the motor attempts to restart again automatically if a start command is
still active following this reset command. This particularly applies if the motor protection has
tripped. For safety reasons, you are advised to integrate the group fault output (terminals
95 and 96) in the controller.
General information
A motor feeder comprises at least a
disconnector
, a
contact element
, and a
motor
.
Line protection against short-circuits must be implemented, together with overload protection
for the line and motor.
Disconnector
The isolating function with line protection against overload and short-circuits can be achieved
with a motor starter protector or a fuse disconnector, for instance.
(For details of fuse and circuit breaker assignment, refer to chapter Feeder component
layout (standard circuit) (Page 270) and chapter Feeder component layout (inside-delta
circuit) (Page 275).