What is difference between ZB5AS74 and ZB5AS934 Emergency stop push buttons
Difference between ZB5AS74 and ZB5AS934 is that ZB5AS934 is Emergency Stop, switching OFF trigger action type push button head whereas ZB5AS74 is Emergency switching OFF push button head and it is not with trigger action.
Differene between the trigger action key release emergency stop and switching off key release emergency stop is as below
1. Emergency stop operation is “an emergency operation intended to stop a process or a movement that has become hazardous”. It is part of the emergency stop function system of the machine.
2. Emergency switching off operation is “an emergency operation intended to switch off the supply of electrical energy to all or part of an installation where a risk of electric shock or another risk of electrical origin is involved ". It is directly linked to risk of electrical origin, related to the machine or not.
For Emergency Stop Trigger Action Pushbutton, yellow color Circular legend with triangular marks must be there which indicates the conformity to standard EN/IEC 60204-1 and EN/ISO 13850:2006 like ZB4 BS844.
With Emergency Switching off type Pushbutton, user can select circular legend without triangular marks.
All rest of the features are common between both of them such as
1. red Ø30 Emergency stop, switching off head Ø22 and latching key release
2. supplied with Ronis key n-455