Glossary · Protective devices and interlocks
Manual reset
In machine safety, a manual reset is a reset initiated by a deliberate human action from a location with adequate visibility and control of the safeguarded area. It confirms that the area is clear before the machine can be restarted.
- Machine safety
- Human factors
In one sentence
A manual reset requires a deliberate action from a point with a clear view of the safeguarded area, so that nobody is left inside when the machine restarts.
Example
After a person has left a robot cell through a light curtain, an operator presses the reset button mounted outside the cell, from where the whole cell is visible, before starting the robot again.
How it applies
- Machine safety: Manual reset is essential where a person can stand inside the safeguarded area without being detected, for example behind a light curtain at a cell entrance or inside a perimeter guard. ISO 13849-1 treats manual reset as a safety function.
- Human factors: Place the reset device outside the hazard zone and where it cannot be reached from inside. Consider human error: a person might reset while a colleague is still inside. Presence detection or personal locks reduce this risk.
- Design: A manual reset must not start the machine by itself. A separate start command follows.
- Technical documentation: Instructions must say where the reset is located and require checking the area before resetting.