- Reaction score
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Because, to the best of my knowledge it is one of the minimum requirements for emergency stops of any type, this isngiverned by legislation and not bs7671. I'm far from an expert on the relevant legislation though so yes I may be wrong.Why ?
If someone is silly enough to leave the key in after going to all the trouble of fitting a key to reset stop.
But you can't design a safety system based on whether it would be silly for someone to do something, these systems need to be designed failsafe and if one possible failure is a key being left in an e-stop then it should be designed out of the system.
The same could be said for a tripped RCD or MCB do we need a separate reset for them as well ?
The same cannot be said for those things, they are completely different and governed by completely different rules!
An MCB or RCD will automatically trip again if the fault still exists, an E-stop will not automatically press itself if reset in error.
If the E-stop fails to latch in the off position for any reason then having it electrically latched and requiring a second deliberate action to reset it will prevent a dangerous situation.