Key Technical Specifications
- Product Model: P1U-1NB
- Manufacturer: Pilz
- Product Type: Safety relay / safety-related control relay
- Nominal Supply Voltage: 230–250 V AC — verify on physical label
- Power Range: 3.5–1100 VA — verify on physical label
- Current Rating: 8 A — verify on physical label
- Contact Configuration: Not confirmed from available references
- Mounting Format: Not confirmed
- Terminal Type: Not confirmed
- Safety Rating / Category: Not confirmed
- Documentation Requirement: Verify against physical label, Pilz datasheet, and machine safety circuit drawing
Product Introduction
PILZ P1U-1NB is a Pilz safety relay intended for industrial machine safety control applications. It is typically used to monitor safety inputs such as emergency-stop circuits, safety gates, light curtains, or other protective devices, and to switch safety-related outputs in a controlled manner.The available listing data points to a 230–250 V AC variant with an 8 A current reference and a 3.5–1100 VA power range. That suggests it is a line-powered safety relay rather than a low-voltage DC module. However, because the exact contact layout, safety performance level, and application category are not confirmed, this unit should be treated as a label-verified replacement part.
Installation & Configuration Guide
Preparation — 10 minutes
- Confirm the removed unit is marked P1U-1NB.
- Check the full label for voltage, VA range, current rating, and any Pilz order number.
- Identify the host safety circuit: E-stop, safety gate, light curtain, interlock, or control relay circuit.
- Obtain ESD protection if the unit contains electronic monitoring circuitry.
- Prepare tools: screwdriver set, label tape, camera, multimeter, and insulation tester if required.
- Review the machine safety drawing before disconnecting anything.
Safety: Follow site lockout/tagout procedures. Safety relays are often part of protective circuits — incorrect wiring can create a serious hazard.
Removal — 5 to 10 minutes
- De-energize the control circuit and, if required, the main power circuit.
- Label all wiring before removal.
- Photograph terminal connections and module orientation.
- Remove input wiring first, then output wiring.
- Release the module from DIN rail, panel, or carrier.
- Inspect terminals, mounting clips, and wiring for heat damage or corrosion.
Installation — 10 minutes
- Compare the old and new P1U-1NB units.
- Confirm label voltage, current, VA range, and terminal layout.
- Mount the relay securely.
- Reconnect wiring exactly according to the original labels and drawings.
- Confirm supply, safety inputs, and safety outputs are connected to the correct terminals.
- Do not force terminals or connectors.
- Check that no stray wire strands are exposed outside terminals.
Power-On & Test — 10 minutes
- Restore control power only after all wiring is verified.
- Check for abnormal heat, noise, or smell.
- Verify that the relay powers up correctly.
- Test the safety function in a safe condition — for example, simulate an E-stop or safety-gate opening.
- Confirm the safety outputs open when required.
- Confirm the relay resets only when the fault condition is cleared and the reset method is satisfied.
- Do not return the machine to production until the safety function is confirmed.
Troubleshooting Quick Reference
| Symptom | Most Likely Cause | First Check |
|---|---|---|
| Relay does not energize | Wrong supply voltage or open fuse | Measure supply at relay terminals |
| Safety output does not open | Faulty output contact or wiring error | Check output wiring and load circuit |
| Relay will not reset | Safety input still active or reset not satisfied | Check E-stop, safety gate, and reset circuit |
| Intermittent faults | Loose terminal or damaged wiring | Tighten terminals and inspect conductors |
| Wrong relay installed | Voltage or contact mismatch | Compare old and new labels |
| Overheating or burning smell | Overload, short circuit, or wrong application | Remove power immediately and inspect |
Dimensions, Mounting & Wiring Notes
- Height × Width × Depth: Not confirmed from available references. Measure the existing unit before ordering.
- Mounting Method: Likely DIN-rail or panel mounting, but confirm from the physical unit.
- Terminal Notes: Confirm terminal layout from the original relay label or Pilz documentation.
- Wiring Notes: Keep safety input wiring separated from high-current power wiring where possible. Use shielded cables if required by the machine safety design.
- Inspection Notes: Look for burnt terminals, cracked housing, missing labels, corrosion, or evidence of incorrect voltage application.
FAQ
What is PILZ P1U-1NB used for?
It is a Pilz safety relay used in machine safety control circuits. Typical uses include monitoring emergency stops, safety gates, light curtains, interlocks, or other protective devices.
Is P1U-1NB a 24 V DC relay?
Not necessarily. The available listing data refers to a 230–250 V AC variant. Do not assume it is 24 V DC without checking the physical label.
Can I replace P1U-1NB with another Pilz safety relay?
Only if the replacement has the same voltage rating, contact configuration, safety function, mounting format, and terminal layout. Safety relays are not always interchangeable by model prefix alone.
I only see “P1U-1NB” on the label. Is that enough to order?
Not safely. You should also confirm the full voltage marking, VA range, current rating, contact arrangement, and any Pilz order or identification number.
What is the biggest risk when buying this part?
The biggest risk is receiving a unit with the wrong voltage, contact configuration, or safety function. Always request photos of the full label, terminals, and mounting side before purchase.
Can this relay be used outside a safety circuit?
It may be possible in some control applications, but P1U-1NB appears to be a safety-related relay. Its main value is in safety monitoring and safety output switching. Confirm the intended application before using it as a general-purpose relay.
How do I test it after installation?
After installation, verify supply voltage, confirm safety inputs are recognized, test the safety stop function, check that outputs open correctly, and confirm proper reset behavior. Do not return the machine to service until the safety function is verified.
