User Guide

3RT1 contactors/3RH1 control relays
SIRIUS System Manual
GWA 4NEB 430 0999-02 DS 01
3-47
3.3.7 3RH1 control relays
Control relays are switching devices for auxiliary circuits for controlling, sig-
naling, and interlocking. Control relays have to meet specific requirements
in terms of clear terminal markings and have a time- and cost-saving termi-
nal system.
The SIRIUS 3RH1 control relays (frame size S00) meet these requirements
Terminal markings The terminal markings comply with EN 50 011 and EN 50 005 (for a more
detailed explanation, see Section 3.4.1 "Auxiliary switches").
Frame size and features 3RH1 control relays are available as follows:
•Frame size S00
With AC or DC operation
Same construction as the motor contactor of frame size S00
4-pole basic version
Can be extended to 8 poles with snap-on auxiliary switch blocks
Screw-type or Cage Clamp terminals
Screw-type terminals The 3RH1 control relays have captive screws (cross-tip Pozidriv, size 2), with
all the terminal points open on delivery. The screwdriver guides allow screw-
driving machines to be used.
Cage Clamp-Terminals The 3RH11 control relays are also available with Cage Clamp terminals - a
screwless terminal system. This type of terminal is particularly suitable if
strong shock or vibration can be expected at the installation location. These
terminals are also suitable for two-conductor connections. All the terminals
are accessible from the front and are easily visible.
Soldering pin
connections
Both the 4-pole basic version as well as the control relays that have an auxil-
iary switch block attached at the front (see Section 3.4, Accessories) can be
soldered onto printed circuit boards using a soldering pin adapter.
Contact reliability All the switching elements of the 3RH1 control relays are equipped with
contact pieces that have particularly high contact stability, ensuring high
contact reliability even at low voltages and currents. This subject is dis-
cussed in detail in Section 3.2.3.2, "Contact reliability".