Product Overview
The Pilz PNOZ X3 (Part Number: 774310) is a standalone safety relay designed for industrial automation applications. As part of the renowned PNOZ X series from Pilz GmbH & Co. KG, this device provides reliable safety-oriented interruption of safety circuits in compliance with international safety standards.
The PNOZ X3 safety relay is specifically engineered for monitoring E-STOP pushbuttons, safety gates, and limit switches. Its robust design and comprehensive safety features make it an essential component in modern industrial safety systems across manufacturing, packaging, material handling, and robotic applications.
Technical Specifications
General Specifications
| Parameter | Specification |
|---|---|
| Part Number | 774310 |
| Series | PNOZ X3 |
| Manufacturer | Pilz GmbH & Co. KG |
| Supply Voltage | 24 V AC/DC |
| Voltage Tolerance | -15% / +10% |
| Power Consumption | 5 VA (AC) / 3.5 W (DC) |
Output Contact Specifications
| Contact Type | Quantity | Configuration |
|---|---|---|
| Safety Contacts (NO) | 3 | 13-14, 23-24, 33-34 |
| Auxiliary Contact (NC) | 1 | 41-42 |
| Semiconductor Output | 1 | Y31-Y32 |
Electrical Ratings
| Parameter | Value |
|---|---|
| AC-15 at 230 V | 5 A |
| DC-13 at 24 V | 6 A (6 cycles/min) |
| AC-1 (240 V) | 8 A |
| DC-1 (24 V) | 8 A |
| Conventional Thermal Current | 6.5 A (3 contacts in use) |
| Max. Short Circuit Current (IK) | 1 kA |
| Semiconductor Output | 24 V DC, 20 mA |
Mechanical Specifications
| Parameter | Value |
|---|---|
| Width | 45 mm |
| Height | 87 mm |
| Depth | 121 mm |
| Net Weight | 375 g |
| Housing Material | PPO (UL 94 V0) |
| Front Housing | ABS (UL 94 V0) |
| Mechanical Life | 10,000,000 cycles |
| Mounting | 35 mm DIN Rail |
| Terminal Type | Screw Terminals (fixed) |
| Wire Cross-Section | 0.20 – 4.00 mm² (24-10 AWG) |
| Torque Setting | 0.60 Nm |
Environmental Specifications
| Parameter | Value |
|---|---|
| Operating Temperature | -20°C to +55°C |
| Storage Temperature | -40°C to +85°C |
| Humidity Rating | 93% r.h. at 40°C |
| Protection Class (Housing) | IP40 |
| Protection Class (Terminals) | IP20 |
| Pollution Degree | 3 |
| Overvoltage Category | III / II |
| Installation Environment | Control cabinet minimum IP54 |
Safety Classification
| Standard | Level |
|---|---|
| ISO 13849-1 (PLe) | Performance Level e |
| EN ISO 13849-1 (Cat) | Category 4 |
| IEC 61508 (SIL) | SIL 3 |
| EN 62061 (SIL CL) | SIL CL 3 |
| PFH Value | 2.31 × 10⁻⁹ |
| Mission Time (TM) | 20 years |
Terminal Configuration
Power Supply Terminals
- A1, A2: AC power supply terminals
- B1, B2: DC power supply terminals (24 V DC)
- FE: Functional Earth (required for AC operation)
Input Terminals
- S11: +24 V internal (common)
- S12: Channel 1 input (CH1)
- S21: 0 V internal (common)
- S22: Channel 2 input (CH2)
- S31: Channel 2 reference (S32 bridged in single-channel mode)
- S32: Channel 2 input
Reset/Start Circuit Terminals
- S13: +24 V start input (internal)
- S14: Start circuit input
- S33: +24 V reset input (internal)
- S34: Monitored reset circuit input
Output Terminals
- 13-14: Safety contact NO #1
- 23-24: Safety contact NO #2
- 33-34: Safety contact NO #3
- 41-42: Auxiliary contact NC (for signaling only)
- Y31-Y32: Semiconductor output (PNP, 24 V DC, 20 mA)
Operating Modes
1. Single-Channel Operation
In single-channel mode, there is no redundancy in the input circuit. The PNOZ X3 detects earth faults in the start and input circuit. This mode is typically used when the target safety level does not require full redundancy.
2. Dual-Channel Operation with Short Circuit Detection
Dual-channel operation provides a redundant input circuit that detects:
- Earth faults in the start and input circuit
- Short circuits in the input circuit
- Shorts across contacts in the input circuit
3. Automatic Start
The unit becomes active immediately once the input circuit has been closed. The safety contacts close and the unit is operational without requiring a manual reset.
4. Monitored (Manual) Start
The unit becomes active only when:
- The input circuit is closed
- The start circuit (S33-S34) is opened and then closed again
- A waiting period of approximately 300 ms has elapsed after input circuit closure
This prevents automatic restart after a power failure or unexpected shutdown.
LED Status Indicators
| LED | Status | Meaning |
|---|---|---|
| POWER | Green ON | Supply voltage present |
| OFF | No supply voltage or fault | |
| CH.1 | Green ON | Safety contacts of Channel 1 closed |
| OFF | Channel 1 open or fault | |
| CH.2 | Green ON | Safety contacts of Channel 2 closed |
| OFF | Channel 2 open or fault |
Timing Specifications
| Parameter | Value |
|---|---|
| Switch-on Delay (Automatic Start) | ≤ 50 ms |
| Switch-on Delay (Monitored Start) | ≤ 50 ms + t4 |
| Delay-on De-energisation | ≤ 15 ms |
| Recovery Time | ≤ 300 ms |
| Waiting Period (Monitored Start) | 300 ms (typ. 35 ms) |
| Response Time on Input Open | ≤ 30 ms |
Typical Applications
E-STOP (Emergency Stop) Circuits
The PNOZ X3 is widely used for monitoring emergency stop buttons in machinery and equipment. When the E-STOP button is pressed, the safety contacts open immediately, cutting power to the machine’s drive system.
Safety Gate Monitoring
Safety gates and guards on machinery can be monitored using safety limit switches or magnetic safety switches. The PNOZ X3 ensures that machine operation is halted when a guard is opened.
Press Control
For presses and stamping machines, the PNOZ X3 can monitor two-hand controls to ensure operator safety during the machine cycle.
Light Curtain Integration
When combined with safety light curtains, the PNOZ X3 provides comprehensive protection for hazardous areas in automated production lines.
Conveyor Safety
The safety relay can be used to monitor emergency stops and safety switches on conveyor systems, ensuring quick shutdown in case of emergency.
Wiring Guidelines
Power Supply Connection (24 V DC)
- Connect B1 to +24 V DC
- Connect B2 to 0 V
- Ensure the power supply complies with SELV/PELV requirements per VDE 0100, Part 410
Power Supply Connection (24 V AC)
- Connect A1 to L (Live)
- Connect A2 to N (Neutral)
- Connect B2 to Functional Earth (FE)
Output Fuse Protection
To prevent contact welding, appropriate fuses should be installed before the output contacts:
| Fuse Type | Safety Contacts | Auxiliary Contacts |
|---|---|---|
| Blow-out fuse, quick | 10 A | 10 A |
| Blow-out fuse, slow | 6 A | 6 A |
| Circuit breaker (24 V AC/DC, B/C) | 6 A | 6 A |
Compatible Alternatives and Substitutes
| Manufacturer | Equivalent Model | Key Differences |
|---|---|---|
| Schmersal | SRB-E-301ST | Similar 3NO output, different terminal layout |
| Sick | UE410-MU3T0 | Extended diagnostics, different form factor |
| Omron | G9SA-301 | Compact design, similar SIL3 rating |
| ABB | CSR-30DC | Different voltage options available |
| Eaton | EMT6 | Similar functionality, wider voltage range |
| Pilz (Same Series) | PNOZ X3P 750103 | Pluggable terminals, same electrical specs |
Certifications and Approvals
- CE: Compliant with European safety directives
- cULus Listed: Certified for use in North American markets
- TÜV: German technical inspection association approval
- CCC: China Compulsory Certification
- KOSHA: Korea Occupational Safety and Health Agency approval
- EAC: Eurasian Conformity marking
- RoHS: 2011/65/EU, 2015/863/EU compliant
- REACH: Registration, Evaluation, Authorization and Restriction of Chemicals
Installation and Maintenance
Installation Requirements
- Install in a control cabinet with minimum IP54 protection
- Mount on 35 mm DIN rail using the rear notch
- For vertical mounting, secure with a fixing element (retaining bracket or end angle)
- Maintain minimum 6 mm clearance between units when using AC supply
- Use copper wire rated for 60/75°C
Maintenance Checklist
- Perform periodic safety function tests as per ISO 13849-1 requirements
- For SIL CL 3 / PL e applications: test at least once per month
- For SIL CL 2 / PL d applications: test at least once per year
- Verify LED status indicators during operation
- Check terminal connections for tightness (torque: 0.6 Nm)
- Inspect for dust accumulation and moisture damage
- Replace unit after mission time (20 years) expires
Ordering Information
| Order Number | Description |
|---|---|
| 774310 | PNOZ X3 24 VAC/DC, 3NO+1NC+1SO, screw terminals |
| 774311 | PNOZ X3 42 VAC, 24 VDC, screw terminals |
| 774312 | PNOZ X3 110 VAC, 24 VDC, screw terminals |
| 774090 | Cover for P-93/P-97 housing (accessory) |
Conclusion
The Pilz PNOZ X3 (774310) represents a robust and reliable safety relay solution for industrial automation applications. With its comprehensive safety features, including SIL 3 / PL e / Cat. 4 ratings, dual-channel operation with short circuit detection, and flexible start modes, this device provides exceptional protection for operators and equipment alike.
Its compact 45 mm width design, easy DIN rail mounting, and comprehensive terminal configuration make it an excellent choice for both new installations and safety upgrades. The extensive certification portfolio ensures global compliance, while the proven PNOZ X series platform offers peace of mind through decades of industrial safety experience.
When selecting a safety relay for your application, consider the PNOZ X3’s balance of functionality, reliability, and ease of integration. For applications requiring pluggable terminals, the PNOZ X3P variant offers the same electrical specifications with enhanced installation convenience.