PL Calculation according to EN ISO 13849-1

4S prepares a written calculation and verification of the Performance Level (PL) of your safety-related control functions in accordance with EN ISO 13849-1 – from category and architecture assessment through to the complete verification report.

What the PL calculation covers

For each safety-related control function – for example an emergency stop, safety guard door monitoring, or two-hand control – the required Performance Level (PLr) is taken from your risk assessment, and the Performance Level (PL) actually achieved by the chosen circuit architecture is verified, including category, MTTFd, diagnostic coverage (DCavg), common cause failure (CCF) and, where required, PFHD. This is based on the harmonised standard EN ISO 13849-1 (Safety of machinery – Safety-related parts of control systems).

Process

  1. You send me the control system documentation – circuit diagram, data sheets of the components used, and the required Performance Level (PLr) for each safety function from your risk assessment.
  2. Identification of the safety functions and assignment of the respective circuit architecture (Category according to EN ISO 13849-1).
  3. Calculation of MTTFd, DCavg, CCF and PL for each safety function, taking into account the manufacturer’s data (B10d values, PFHD values).
  4. You receive the written verification report with all calculated values, proof of PL ≥ PLr for each safety function and, if the required Performance Level is not achieved, a recommendation for improvement.

Who this is for

For manufacturers of machinery and control systems, control cabinet builders and integrators who need proof of the Performance Level for their safety-related control functions – as part of the technical documentation or independently of it, for example following a component change in an existing control system.

Also useful

Whether a safeguard maintains sufficient distance from the hazard zone can already be documented in advance and comprehensibly with the free calculators for EN ISO 13855 and EN ISO 13857.

Practical knowledge on Performance Level and functional safety is also covered in our machinery safety workshops.

Not sure whether your safety functions achieve the required Performance Level? Contact 4S – I will help you with the standard-compliant calculation and documentation.