Plug-In Relay Coupling Links - Siemens sirius System Manual

3RH, 3TX, LZX coupling links

6.2.3 Plug-in relay coupling links

Models
Widths
Installation
Surge suppression
Connection
Test button
LED
Power consumption
Safe isolation
6-6
The Plug-in relay coupling links are modular coupling links. The plug-in for-
mat means the relays can be easily replaced.
There are complete modules for 1 and 2 changeover contacts and individual
modules for 1, 2, 3 or 4 changeover contacts for a rated control supply volt-
age of either 24 VDC or 230 VAC.
Plug-in relay coupling links are available in 3 widths:
• 15.5 mm print relays, LZX: RT variants
• 27 mm mini-industrial relays, LZX: PT variants
• 38 mm industrial relays, LZX: MT variants
The plug-in relay coupling links are plugged into the associated bases, and
these are snapped onto a 35 mm rail in acc. with EN 50 022.
To avoid high breaking voltage peaks, LZX: RT and PT plug-in relay coupling
links are available for a rated control supply voltage of 24 VDC, with 1, 2, or
4 changeover contacts (Ws) and integrated surge suppression (flywheeling
diode). RC elements are available for AC voltages.
The standard polarity must be taken into consideration when connecting up:
• At A1: positive voltage supply (+)
• At A2: negative voltage supply (-)
The LZX: PT and MT variants are equipped with a test button. The plug-in
relay coupling link can thus be brought into the switching state and locked
without the need for electrical triggering. When the test button is protrud-
ing, this indicates the locked switching position.
An LED is available either as an individual plug-in module or is integrated in
the relay, depending on the variant involved.
Following on from the technical specifications of the electronic systems, the
coupling links have low power consumption.
The drive circuit and contacts are electrically isolated. Safe isolation can also
be achieved for the print relays (LZX:RT series) by means of a special base.
SIRIUS System Manual
GWA 4NEB 430 0999-02b