User Manual

SIRIUS 3RU2/3RB3 overload relays
5.8 Operation
SIRIUS Innovations
System Manual, 01/2011, A8E56203870002-03
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5.8.2 Setting the tripping class/ground-fault detection (3RB31)
In the case of the 3RB31 solid-state overload relay, it is also possible to select the tripping
class (CLASS 5, 10, 20 or 30) via a second rotary knob using a screwdriver and activate or
deactivate internal ground-fault monitoring.
There are 8 possible settings:
● CLASS 5 , 10, 20, and 30 without ground-fault detection (STANDARD)
● CLASS 5 , 10, 20, and 30 with ground-fault detection (Gnd-FAULT)
5.8.3 RESET after release
Manual and automatic reset
If manual reset is selected, resetting can be carried out directly on the device by pressing the
RESET button.
R
E
S
E
T
A remote reset (remote RESET) is possible in conjunction with the mechanical and electrical
RESET modules, which are available as accessories. If automatic RESET is set on the
overload relay, the relay will be reset automatically. A relay can only ever be reset after the
recovery time has elapsed.
WARNING
Automatic machine restart!
Can result in death, serious injury, or property damage.
If a switch-on command is present after an overload trip and a manual reset or automatic
reset is performed, the machine will start up immediately. People may be injured if they stay
in the danger area of the machine.
Make sure that the motor does not start up again following an overload trip until a new
switch-on command has been issued (e.g. via an additional ON button) and that no one is
in the machine danger zone at the time of restarting.