During technical comparisons, RLY3-OSSD400 appears alongside Sick Diffuse Sensor, Sick Rly3 Ossd100 and Sick Safety Relay so engineers assess signal types, ingress protection, and ambient tolerances accurately.
Sick RLY3-OSSD400 Safety Relay
The RLY3-OSSD400 is a reliable Sick Programmable Safety Relaydesigned for industrial automation systems requiring high-performance signal switching and monitoring. This SIL 3 certified relay offers safe control of OSSD-enabled safety sensors with robust electrical protection.

| Brand | Sick |
| Product Type | Safety Relay |
| Product | RLY3-OSSD400 |
Sick RLY3-OSSD400 Safety Relay β Technical Specifications
| Specification | Value |
|---|---|
| Compatible sensor types | Safety sensors with OSSDs |
| Safety integrity level | SIL 3 (IEC 61508) |
| Category | Category 4 (ISO 13849-1) |
| Performance level | PL e (ISO 13849-1) |
| TM (mission time) | 20 years (ISO 13849-1) |
| Sensor monitoring | - |
| Restart interlock | - |
| Reset | - |
| External device monitoring (EDM) | β |
| Connection type | Front connector with spring terminals |
| Inputs | 2 safety inputs |
| Outputs | 4 enabling current paths (safe), 1 feedback current path (for use as external device monitoring, not safe), 1 signaling current path (not safe) |
| Display elements | LEDs |
| Configuration method | - |
| Supply voltage VS | - |
| Residual ripple | - |
| Power consumption | β€ 2.5 W (DC) |
| Input voltage HIGH | 24 V DC (11 V ... 30 V) |
| Input voltage LOW | 0 V DC (β3 V ... 5 V) |
| Input current | β€ 60 mA |
| Test pulse width | β€ 1 ms |
| Test pulse rate | β€ 10 Hz |
| Response time | 12 ms |
| Type of output | N/O contacts, positively guided |
| Contact material | Silver alloy, gold flashed |
| Switching voltage | 10 V AC ... 230 V AC, 10 V DC ... 230 V DC |
| Switching current | 10 mA ... 6 A |
| Total current | 12 A |
| Overvoltage category | III (EN 60664-1) |
| Rated impulse withstand voltage Uimp | 6 kV (EN 60664-1) |
| Output voltage HIGH | - |
| Output voltage LOW | - |
| Input current (NPN) | - |
| Output current (PNP) | - |
| Output voltage | - |
| Test pulse interval | - |
| Dimensions (W x H x D) | 28 mm x 124.6 mm x 85.5 mm |
| Enclosure rating | IP20 (IEC 60529) |
| Ambient operating temperature | β25 Β°C ... +55 Β°C |
| Storage temperature | β25 Β°C ... +70 Β°C |
| Air humidity | β€ 95 %, Non-condensing |
| Interference emission | According to IEC 61000-6-4 |
| Interference resistance | According to IEC 61326-3-1, According to IEC 61000-6-2, According to IEC 60947-5-1 |
| Weight | 180 g |
Built for demanding industrial safety applications, the RLY3-OSSD400 is a reliable Sick Programmable Safety Relay integrates seamlessly with OSSD-compatible sensors to provide advanced switching capabilities while ensuring safety compliance. With certification to SIL 3 (IEC 61508), PL e (ISO 13849-1), and Category 4 standards, it ensures consistent performance and system protection throughout its 20-year mission time.
This programmable safety relay features 2 safety inputs and a robust output configuration including 4 enabling current paths (safe), 1 feedback current path (for external device monitoring), and 1 signaling output. The relay is equipped with N/O positively guided contacts made from silver alloy, gold flashed, supporting 10 V to 230 V AC/DC switching at up to 6 A, making it ideal for high-current switching scenarios.
Operating on a 24 V DC supply (11β30 V DC), the relay consumes just β€ 2.5 W, with an input current of β€ 60 mA. It achieves a fast 12 ms response time and includes LED indicators for quick status diagnostics. Built with a front connector using spring terminals, this unit simplifies installation and maintenance in tight control panel layouts. The compact housing (dimensions: 28 mm x 124.6 mm x 85.5 mm) is rated IP20, suitable for protected enclosure use. Its robust construction and EMC compliance (IEC 61000-6-4, IEC 61326-3-1) ensure stable operation even in electrically noisy environments.
Operating reliably in ambient temperatures from β25 Β°C to +55 Β°C and up to 95% humidity, the RLY3-OSSD400 is trusted across sectors such as packaging, robotics, and machine tool safety. View full specifications here or request your quote today to experience our unmatched support and pricing advantage.




