Siemens Sirius 3RH1140-1BB40 10 AMP AC Control Relay with 4 normally open contacts and a 24 volt DC coil. This 4 pole relay comes with screw terminals, is finger safe and in an IP20 enclosed degree of protections with optional terminals covers. In addition to the base 4 normally open contacts, a top mounted auxiliary contact can be added for an additional four poles in any contact sequence from 4 N.C. to 4 N.O. Varistors, RC elements and diodes can be plugged into the front of this Siemens control relay for dampening opening surges on the coil. For different contact arrangements, Siemens also offers the 3RH1122-1BB40, with 2 normally open and 2 normally closed contacts along with the 3RH1131-1BB40 which has 3 normally open and 1 normally closed poles for switching.
|Number of poles||4|
|Coil voltage||24 volt DC|
4 normally open
“Safety” Control Relays
Safety rated control relays are required to have positively driven contact elements according to IEC 60947-5-1 Annex L. Positively driven contact elements are a combination of NO auxiliary contacts and NC auxiliary contacts whose construction prevents them from being closed simultaneously. In some industries, such as automotive, requirements have been established that a safety rated control relays must also have permanently mounted auxiliary contact blocks.
Siemens Control Relays for “Safety” applications:
All SIRIUS 3RH1 control relays (with at least 1 NC contact) meet or exceed the criteria for "Safety Control Relays” according to IEC60947-5-1 Annex L. This is true for the basic 3RH relay with or without an additional auxiliary contact block.