Pilz PNOZ compact Pnoz c1/c2 Safety Relay Configuration
PNOZ S4 is a best-selling safety relay in the PNOZsigma series from Pilz. This product is easy to install, has rich functions, and supports a variety of safety circuit configurations. It is equipped with a variety of wiring methods for quick integration and is widely used in industrial safety scenarios such as emergency stop, safety door control, and light curtains.
Type | PNOZ s1 | PNOZ s2 | PNOZ S3 | PNOZ s4 | PNOZ s4.1 |
E-STOP | √ | √ | √ | √ | √ |
Safety gate | √ | √ | √ | √ | √ |
Light curtain | √ | √ | √ | ||
Performance level (PL) | c | e | e | e | e |
Safety integrity level (SIL) CL | 2 | 3 | 3 | 3 | 3 |
Output contacts (safe) | 2 | 3 | 2 | 3 | 3 |
Width in mm | 12.5 | 17.5 | 17.5 | 22.5 | 22.5 |
Special approvals | - | - | - | - | Burner control/
burner management EN 50156-1 |
Next, we will briefly introduce the parameter settings of the PNOZ X.8P safety relay.
Application and Characteristics of Emergency Stop Relay

In addition to emergency stop buttons, safety doors, light curtains, two-hand control devices and timed safety monitoring, the PNOZsigma series also supports special functions such as speed monitoring and safe braking, with a wider range of adaptability. Some models can operate stably in plateau environments with an altitude of up to 5,000 meters.
1. Fast installation: with push-in spring terminals
2. 20% less wiring effort: connectors for extended contacts
3. Simple configuration: the design and position of the terminals are identical for all device versions: connections and devices can therefore always be quickly assigned during configuration, installation and diagnostics
4. Maximum flexibility: selectable operating modes and timer function
5. Fast diagnostics: via 6 LEDs - no external measuring devices required
6. Fast assembly via spring clips: no tools required
7. Tamper-proof: setting elements with lockable covers
Basic Description of LED Indicator Function
Text description | State | Functional Description |
POWER | Always on | Power status indicator |
IN1 | Always on | Input circuit of channel S12 is closed |
IN2 | Always on | Input circuit of channel S22 is closed |
OUT | Always on | The safety contacts are closed and the semiconductor output Y32 carries a high signal |
RESET | Always on | Reset S34 terminal carries 24 VDC high level signal |
Fault | Always on | External fault: Plug terminals not connected |
Flash | Internal Fault |
Terminal Function Description

Terminal number | Functional Description |
A1、A2 | Power supply |
S11、S52 | Safety input channel 1 |
S21、S22 | Safety input channel 2 |
S12、S34 | Startup circuit (reset mode) |
13、14 | Safety contacts |
23、24 | Safety contacts |
33、34 | Safety contacts |
41、42 | Auxiliary contacts |
Dip Switch Configuration Table


①:Single-channel operation
②:Dual channel operation
③:Autostart (reset)
④:Falling edge type monitored start
⑤:Monitored startup with rising edge type
⑥:Starts with the startup test: The unit checks whether a closed safety door opens when supply voltage is applied and then closes again.
Specific description:
Single channel operation
The input circuit has no redundant design and can detect ground faults in the start-up circuit and the input circuit.
Dual-channel operation
1. Without contact short circuit detection
2. Redundant input circuits are used to detect ground faults in the start circuit, input circuit, and short circuits in the input circuit and monitored start circuit.
3. With short-circuit detection between contacts: Based on the above functions, the short-circuit detection function between input circuit contacts is added.
Startup mode
1. Automatic start: The unit is activated directly when the input circuit is closed.
2. Manual start: The unit will be activated only when the input circuit and the start circuit are closed at the same time.
3. Monitored start:
· Falling edge trigger: Falling edge trigger
· Rising edge trigger: After the input circuit is closed, the start circuit is then closed and opened, and the unit is activated; or the input circuit is closed and the start circuit is closed and then opened again, the unit is activated.
· Start test: When the unit is powered on, it will detect whether the safety door is opened and closed again in the closed state.
Note: Some of the information in this article is referenced from Pilz brand public information, which is intended to share industry technology and interpret products. The copyright belongs to the original company and will be deleted if infringed.
Related Safety Products
👉 Want to know about safety relays suitable for scenarios such as safety doors, light curtains and emergency stop buttons? Welcome to check out our recommended products: