The Principles of Safe Industrial Power Design (Download)
In safety-related industrial systems, the power supply is one of the most critical pieces of the puzzle, and it must be protected against failures that could prevent the system from achieving or maintaining a safe state. However, as outlined by the IEC 61508 standard for functional safety, different failures can prevent safety-related systems from reaching a safe state during startup or operation. Understanding these failure modes — and how to mitigate them — is fundamental to safe power-supply design.
A safety function can either carry out positive actions to avoid hazardous situations or prevent actions from being taken to maintain a safe state. In terms of failures, a safety function could either have a systematic failure or a random one.
