The Pilz PNOZ is a widely deployed industrial automation product family, found in production equipment, building services and OEM machines around the world. Because it is installed in huge numbers, it is also one of the most requested replacement and surplus items on the secondary market. This page explains what the family covers, the variants that matter when replacing one unit, how to identify the exact model, and what to confirm before ordering.
What the Pilz PNOZ family covers
The PNOZ designation groups Pilz products used as safety relay. Within the family, variants differ by rating, I/O or axis count, communication option and hardware revision — which is why the complete ordering code, not the family name, decides what you receive.
How to read the PNOZ ordering code
Ordering codes across major automation brands encode the variant in a predictable structure. When sourcing a Pilz PNOZ unit, extract and confirm these fields from the nameplate:
| Field | What it tells you | Risk if wrong |
|---|---|---|
| Series / base type | Product generation and platform | Wrong accessories, wrong spares |
| Rating suffix | Power, current, I/O count or axis count | Unit cannot carry the load |
| Voltage class | Mains and control voltage | Immediate damage at power-up |
| Communication option | Fieldbus or Ethernet port fitted | Will not join the existing network |
| Revision / index | Hardware generation | Firmware or project incompatibility |
| Regional code | Certification and market variant | Import or compliance problems at destination |
Common field failures and what they indicate
- Power-up failure — often the power supply section or an input stage; test at rated voltage before shipping a replacement into service.
- Communication loss — check port, cable, protocol configuration and grounding before blaming the unit; a large share of "dead ports" are wiring or termination issues.
- I/O or channel faults — verify with loop-powered signals; LED indication alone does not prove a channel.
- Configuration or battery loss — controllers with battery-backed RAM lose programs when the battery fails; keep a project backup, not just a spare unit.
Replacement checklist for Pilz PNOZ
- Record the complete model string from the nameplate — all suffixes, including dashes.
- Photograph the nameplate, the wiring side and any revision sticker.
- Confirm the application context: new build, running spare, or replacing a failed unit.
- Check whether the installed firmware or project must be reproduced, and keep a backup.
- Confirm destination country and required certification.
- Request factory test results and warranty terms with the quote.
The RFQ checklist for Pilz PNOZ
Industrial suppliers quote from the complete ordering information, not from a category name. A complete request contains five elements, and requests that miss one of them usually cost a full round trip:
- Brand and complete model number — every suffix, dash and letter. A partial model number produces a "please confirm" reply instead of a price.
- Quantity — unit price changes with quantity, and lead time depends on it.
- Destination country — determines shipping cost, import duty and the regional variant you should receive.
- Application or replacement context — "replacing a failed unit on a 2016 packaging line" tells the supplier which revision is compatible.
- Nameplate photo — when the label is worn or the number is uncertain, a clear photo resolves more questions than any description.
Send the code from the nameplate, or a photo of it, and a qualified supplier can check availability, confirm compatibility and quote — usually within one working day.
Why factory testing matters when buying automation parts
On the secondary and surplus market, a large share of returns come from parts that powered up but failed under load. Professional suppliers reduce that risk with a documented test routine before shipment:
- Power-up test at rated voltage, current draw recorded
- Port and communication test with the relevant protocol where applicable
- I/O or channel test with loop-powered signals, not just LED checks
- Firmware and parameter verification against the nameplate data
- Cosmetic inspection with photos of the actual unit sent before dispatch
Ask whether testing is included, and whether a warranty applies. A 12-month warranty on tested parts is the market standard for reputable suppliers of refurbished and surplus automation equipment.
Frequently asked questions
My Pilz PNOZ is discontinued. What are my options?
Three, in order of preference: a new-in-box surplus unit from stock, a factory-tested refurbished unit with warranty, or a like-for-like upgrade within the same family. All three can keep a line running; the choice is usually lead time versus budget.
How do I know which PNOZ variant fits my machine?
The nameplate code plus the application context. If the original unit is available, the exact code is the answer. If it is scraped, photos of the unit and the surrounding wiring usually let a supplier reconstruct the variant.
Is a refurbished Pilz PNOZ acceptable for production?
For maintenance and downtime recovery, yes — when the unit is factory tested with a documented routine and carries a warranty. Many plants standardize on tested refurbished units for exactly this reason.
What information gets the fastest quote?
Complete model number, quantity, destination country, and one photo of the nameplate. Requests in that format typically receive availability, compatibility confirmation and pricing in a single reply.