Operation
9.4 TEST function
SIRIUS Innovations - SIRIUS 3RU2 thermal overload relays / SIRIUS 3RB3 solid-state overload relays
80
Manual, 09/2014, A5E03656507420A/RS-AA/002
9.4
TEST function
Test function for the 3RU21 thermal overload relay
Correct functioning of the operational 3RU21 thermal overload relay can only be checked
with the TEST slide. The tripping of the relay can be simulated by moving the slide with a
screwdriver. This simulation process opens the NC contact and closes the NO contact,
thereby checking that the auxiliary circuit has been wired to the overload relay correctly.
Figure 9-2
Executing a device test
Resetting
If the overload relay has been set to automatic RESET, the overload relay is automatically
reset when the TEST slide is released. The relay must be reset with the RESET button if it
has been set to manual RESET.
Figure 9-3
Resetting following device test