The Siemens 3RK1304-0HS00-7AA0 is a SIMATIC safety local isolator module, designed to sit between the motor starter and the control network in a distributed safety architecture. It provides a local isolation point that opens the load circuit in a safe state, meaning when the safety function is triggered, the power path to the motor is physically broken — not just a logic-level signal. This is a key distinction from a standard contactor: the isolator module guarantees galvanic separation at the load terminals. Communication is dual-protocol: PROFINET and PROFIBUS DP are both supported, so it drops into either a PN or PB line without a gateway. The module presents 1 byte of input data and 0 bytes of output data — it reports status but does not consume cyclic output data from the controller.
Power Supply and I/O — What Connects Where
Supply voltage is 24 V DC nominal, with a permissible range of 20.4 to 28.8 V DC. The module draws its control power from this 24 V bus; the motor power path is the separate 400 V AC circuit through the main energy infeed socket (ISO23570). Two digital inputs are provided for external safety signals (e.g., E-stop, guard door switches). All four input signal connections use M12 sockets — standard 4-pin or 5-pin M12 connectors, depending on the sensor wiring. There are no digital outputs on this module; it is a pure input-and-isolation device. Mounting is by screw fixing in any orientation.
Vibration resistance is 2 g; shock resistance is 15 g for 11 ms. These figures mean the module can be mounted on a machine frame or conveyor section that experiences moderate vibration and occasional impact — it is not a fragile panel-only component. MTTFd is listed at 100 a. The safe state is load circuit open.