Siemens SIRIUS 3SK1

14.4.2 3SK1 safety relay wired with 3RM1 Failsafe motor starter
The 3RM13 Failsafe motor starter (230 V supply voltage) is connected to a 3SK1 safety relay.
The two directions of rotation are switched on and o󹪜 operationally via IN1 and IN2, e.g. with
separate switches.
WARNING
Bypassing the safety function in the event of a fault with 3RM11/3RM13 Failsafe motor
starters with 110 to 230 V AC/110 V DC control supply voltage
The control signal for the control inputs in the case of 3RM11/3RM13 Failsafe motor starters
with 110 to 230 V AC control supply voltage must come from A1. Otherwise, the safety
function is bypassed in the event of a fault. Thus, only relay outputs are admissible when using
a PLC.
Do not use a separate control voltage. Only use the relay outputs when using a PLC.
The control supply voltage (L1 and N) to the motor starters is deactivated by the 3SK1 safety
relay and the system is in a safe state.
Note
SILCL 3 in accordance with EN 62061, PL e/Cat. 4 in accordance with EN ISO 13849‑1
A safety-related application up to SILCL 3 to EN 62061, PL e/Cat. 4 to EN ISO 13849‑1 can be
realized in this way.
To achieve SILCL 3/PL e/Cat. 4 for the safety-related application, all components of the safety
functions (detecting/evaluating/reacting) must be designed accordingly.
Note
A fuse must be 󹪝tted as short-circuit protection (4 A gL/gG) in the supply line to the supply
voltage of 3RM1 (L1).
Circuit diagrams
14.4 Typical circuits of 3SK1 safety relays with 3RM1 Failsafe motor starters
SIRIUS 3SK1 Safety Relays and 3RQ1 Positively-Driven Coupling Relays
224 Equipment Manual, 05/2021, A5E02526190021A/RS-AE/005