CU's

[Digit]

If I were going to do it I would install a suitable contactor/relay within the CU connected to a suitable number of latch stop buttons wired in series. Hitting anyone of them would drop the contactor out thus cutting the supply to all appropriate circuits.

Roy.

 

[WoodAddict]

If I were going to do it I would install a suitable contactor/relay within the CU connected to a suitable number of latch stop buttons wired in series. Hitting anyone of them would drop the contactor out thus cutting the supply to all appropriate circuits.

Roy.

This is what I was saying earlier about control circuits with relays and contactors. Anything is doable, it's just down to cost and whether it's worth the extra.

 

[Digit]

Worth the extra? Dunno. My grandson, aged three. wanders in and out of my shop regularly. In my case I isolate a machine immediately after use, pure habit now, and stop any machine that is running as soon as anyone enters.
For some people the extra cast and complication may well be worth it. One of the reasons that I do not use the common 16 amp units is the absence of a switch.

Roy.

 

[Tintin]

if you wired a red button to induce an earthing fault - that would cause the RCD to trip and kill the entire circuit.

This is esentially how the RCD is tripped when you press the test switch on RCD sockets and plugs. It creates an inbalance between the current flowing in the live and neutral wires which trips the RCD.

 

[Digit]

And the reason for the test button is, of course, that RCDs do fail, in fact I replaced my shop one for that very reason earlier this year.

Roy.

 

[WoodAddict]

the test button on an rcd only tests the mechanical operation of the switch. If you don't test periodically then metal parts and springs can become slow and less effective, and in the worse case seize in the on position and never trip at all.

 

[Digit]

Yep! DAMHIK!!!!!

Roy.