Operation; General Information - Siemens sirius System Manual

Coordination type 2
Contactors with over-
load relay

3.2.3 Operation

3.2.3.1 General information

Ambient temperature
Degree of protection
SIRIUS System Manual
GWA 4NEB 430 0999-02b
After short-circuit disconnections, there must be no damage to the load
feeder devices. The only exception is if the contactor contacts have been
welded and can be easily separated again without distorting the contact
pieces.
If contactors are combined with an overload relay, a smaller fuse as speci-
fied in the NSK catalog on permissible short-circuit protection fuses for
motor starters should be used.
The information required to ensure unwelded fusing of the contactors is
contained in the NSK catalog.
The 3RT10 contactors are designed for use in ambient temperatures of
-25 °C to +60 °C. Some variants can be used in temperatures of -35 °C to
+70 °C.
The degree of protection of the SIRIUS contactors is IP20.
Warning
When the supply voltage and load are present, the contactor must not be
actuated by pressing the contact support. It is permissible, however, to
carry out tests with an extra-low test voltage (e.g. ≤ 24 V).
3RT1/3RH1 contactors
3-13