XPSMC32ZP Programmable Safety Controller

The XPSMC32ZP is a programmable safety controller from Schneider Electric’s Preventa series, designed to monitor emergency stops, safety gates, light curtains, and two-hand controls. It meets SIL 3 (IEC 61508) and PL e (ISO 13849-1) standards for high-risk machinery.

Input and Output Configuration

The unit provides 32 safety inputs that can be configured as digital (24 VDC, type 1 or 3) or as OSSD pairs for light curtains. Inputs are divided into 4 isolated groups, each with independent test pulse generation to detect cross faults. There are 8 solid-state safety outputs (24 VDC, 0.5 A each) plus 2 auxiliary non-safe outputs for status indication. All safety outputs are dual-channel with redundancy.

Logic and Programming

Programming is performed using the XPSMCWIN software (Windows based), which supports function block diagrams for safety logic. Pre-certified function blocks include: emergency stop, guard monitoring, muting, bypass, and delay-on/off timers. The controller has 128 KB of flash memory for user programs and 16 KB for persistent variables. Program download is via USB or RS-232 serial interface.

Response Times and Diagnostics

Maximum reaction time from input change to output de-energization is 20 ms (typical 6 ms). The XPSMC32ZP performs continuous self-diagnostics including input short-circuit detection, output cross-channel monitoring, and clock frequency verification. Diagnostic events are stored in non-volatile memory with a time-stamped log (up to 200 entries). A 7-segment display and LEDs indicate operational status and error codes.

Installation and Wiring

The controller mounts on a 35 mm DIN rail and requires 150 mA from a 24 VDC SELV power supply (max ripple 5%). Terminals are removable spring-cage type (0.2–2.5 mm²). Safety inputs require shielded cables for runs longer than 30 meters. The XPSMC32ZP supports both single-channel and dual-channel wiring with or without pulse testing. For Category 4 / PL e systems, dual-channel configuration with cross‑fault monitoring is mandatory.

Standards and Certification

Certified according to EN/ISO 13849-1 (PL e), EN/IEC 62061 (SIL CL 3), EN/IEC 61508 (SIL 3), and EN 60204-1 for electrical safety of machinery. The controller also complies with UL 508 and CSA C22.2 No. 142 for North American markets. No routine calibration is required; the unit is maintenance-free except for periodic visual inspection.

Typical Safety Applications

Common configurations include: emergency stop circuit with 2 NC contacts, gate switch with solenoid locking, light curtain with muting for pallet conveyors, and two-hand control panel (type III). The XPSMC32ZP can be interconnected with other safety controllers via cross-synchronization lines or with standard PLCs via the auxiliary outputs.

Fault Handling and Reset

Upon detection of a safety violation or internal fault, outputs are forcibly switched off within the specified reaction time. Manual reset (monitored) is required to restart the machine; auto‑reset can be configured for non‑hazardous applications. A reset input with edge detection ensures intentional restart. The controller also supports start‑up testing to verify that all safety devices are functional before operation.