A machine consists of several individual machines and each of these machines is fitted with a separate controller. There is also a higher level controller/control centre. When the emergency stop is operated, does the emergency stop command have to be reset on each individual machine or can the active emergency stop command be reset for the individual machines from the higher level control centre, in order to restart the plant?
The requirements for this question come from Clause 4.1.6 of DIN EN ISO 13850. This document states that the emergency stop must be reset at the location at which it was initiated. "Unaffected" emergency stop pushbuttons do not need to be reset.