functional safety

ISO 13849-1 PL Levels: What They Mean in Practice

ISO 13849-1 Performance Levels (PLa to PLe) define how reliable a safety function must be. Learn how PL is determined, how it compares to SIL, and what it means for your machine design.

Jul 24, 2026 · 9 min read

Emergency Stop Circuit Wiring: Categories Explained

Learn how emergency stop circuits are wired, what ISO 13850 categories mean in practice, and how dual-channel monitoring actually works on real hardware.

Jul 13, 2026 · 10 min read

Safety Relay Wiring: Circuits Explained

Safety relay wiring demystified: terminal functions, dual-channel E-stop circuits, feedback loops, manual vs automatic reset, and how the safety output connects to a PLC.

Jul 1, 2026 · 8 min read

IEC 62061 PFHd Calculation: A Step-by-Step Guide

PFHd is the number that decides whether your safety function hits SIL 2. Here is how to calculate it correctly under IEC 62061, with a real worked example.

Jun 27, 2026 · 8 min read

IEC 62061 SIL Levels: What They Actually Mean

IEC 62061 SIL levels define how reliable your safety function must be. Here's what SIL 1, 2 and 3 really mean, how PFH is calculated, and common mistakes to avoid.

Jun 27, 2026 · 8 min read