Mounting; Mounting Options; Minimum Clearances And Mounting Position - Siemens SIRIUS 3RT Series System Manual

SIRIUS 3RU2/3RB3 overload relays

5.6 Mounting

5.6 Mounting
5.6.1

Mounting options

Mounting options for the 3RU21
3RU21 thermal overload relays are matched to 3RT contactors in terms of their electrical
and mechanical features. As a result, direct mounting can be achieved easily. Alternatively,
the devices are suitable for stand-alone assembly.
Mounting options for the 3RB30/3RB31
3RB30/3RB31 solid-state overload relays are suitable for space-saving, direct mounting onto
3RT contactors as well as for stand-alone assembly.
5.6.2

Minimum clearances and mounting position

Minimum clearance
A minimum lateral clearance of > 6 mm must be maintained from grounded parts.
Mounting position for 3RU21 thermal overload relay
The diagrams below illustrate the permissible mounting positions for contactor mounting and
stand-alone assembly in the case of 3RU21 thermal overload relays.
Table 5- 13
The set value is 1.1 times the motor current for a mounting position in the hatched area.
Mounting position for 3RB30/3RB31 solid-state overload relay
For 3RB30/3RB31 solid-state overload relays any mounting position can be chosen as
required.
508
Permissible mounting positions for the 3RU21
Overload relay, stand-alone assembly Contactor + overload relay
SIRIUS Innovations
System Manual, 01/2011, A8E56203870002-03