workshop emergency switching

[overskilled]

So given my workshop is almost finished and with the possibility of my old man using it and doing something stupid (which he has an amazing talent for), I'm trying to reduce the chances of shelling out for a pinebox for him...

What I'm considering is an emergency stop switch (supplied by a 6a breaker), wired into a 40A 3 pole contactor to kill the 16A commando socket, and the 2 x 20Amp radials in one fell swoop. (all the above protected by individual RCBOs - for man paranoid about electricity, he is notorious for using stuff that needs sorted/binned...so because I can't keep an eye on him constantly....I'm planning on protecting him from himself...)

I'm right in thinking diversity can be applied to a contactor?

(workshop install is all single phase, 40Amp submain taken from main house board)

Any gaping holes in my plans?

 

[ipf]

Presumably supplying the control circuit from the 6amp breaker.....or just run the supply via an isolation switch, easily to hand. Can't see why it's needed, though.
Where does the diversity come in?

 

[Sintra]

So given my workshop is almost finished and with the possibility of my old man using it and doing something stupid (which he has an amazing talent for), I'm trying to reduce the chances of shelling out for a pinebox for him...

What I'm considering is an emergency stop switch (supplied by a 6a breaker), wired into a 40A 3 pole contactor to kill the 16A commando socket, and the 2 x 20Amp radials in one fell swoop. (all the above protected by individual RCBOs - for man paranoid about electricity, he is notorious for using stuff that needs sorted/binned...so because I can't keep an eye on him constantly....I'm planning on protecting him from himself...)

I'm right in thinking diversity can be applied to a contactor?

(workshop install is all single phase, 40Amp submain taken from main house board)

Any gaping holes in my plans?

Not getting the bit about diversity as the contactor can handle 40A per pole. Also if each circuit has its own 30mA RCBO then surely these will operate long before you or your father have time to press an E stop button.

 

[tazz]

Would say diversity does not play any part here.....Taking account of the risks does...so installing fail safe emergency stops is ok, but what you are stopping, or more to the point what equipment plays a big roll. Darkwood will corrected me here, but you need to think of equipment which can over run, and may need possible mechanical braking to equipment which stops instantly when power is cut.

 

[UKMeterman]

So given my workshop is almost finished and with the possibility of my old man using it and doing something stupid (which he has an amazing talent for), I'm trying to reduce the chances of shelling out for a pinebox for him...

What I'm considering is an emergency stop switch (supplied by a 6a breaker), wired into a 40A 3 pole contactor to kill the 16A commando socket, and the 2 x 20Amp radials in one fell swoop. (all the above protected by individual RCBOs - for man paranoid about electricity, he is notorious for using stuff that needs sorted/binned...so because I can't keep an eye on him constantly....I'm planning on protecting him from himself...)

I'm right in thinking diversity can be applied to a contactor?

(workshop install is all single phase, 40Amp submain taken from main house board)

Any gaping holes in my plans?

Some items can be stopped a lot faster with a DC injection brake rather than just cutting the power.. contact the manufacturer of the tools.

 

[amlu]

i have my workshop on a radial circuit and there is a Big Red Switch, (40a shower switch scrapped on some job).
it shuts down all power in there.

 

[overskilled]

Been at the shandy so thoughts earlier not as clear as they could be...

was thinking (for some reason) 40A total rather than per pole (too much alcohol...perhaps?)

mainly handheld kit, but if the worst happens wouldn't mind being able to kill the lot with one button push

Will look into DC injection also as there's a few bits of kit I fancy, (as yet unfunded)which dc injection would help with...

thanks..going to go sleep the drink off...

 

[R G]

I did the same in a school food tech room with 4 x EM Stops & 3 pole 100A contactor for 3 Phase D/B ,thats what was specified , diversity is not taken into account ..

The lighting was controlled by a separate D/B..

 

[overskilled]

i have my workshop on a radial circuit and there is a Big Red Switch, (40a shower switch scrapped on some job).
it shuts down all power in there.

What I want to do is, leave the lights on, but kill the sockets, otherwise would just isolate the supply incomer...plus I've got an E stop switch sitting here, only rated to 10amps though according to the internals

 

[Knobhead]

As Sintra suggested. Three pole contactor, one pole per circuit.

Now my suggestion, depending on the area. Several e-stop P/B’s dotted around the place so they’re in easy reach. The e-stop circuit needs to be latched with one reset P/B.

I like the idea that you’re trying to look after the old man. My father in law was a bloody menace given power tools, other than nail his feet to the floor you couldn’t stop him.

 

[netblindpaul]

Look @ BS4163 for a formal implementation of such a system to get the ideas of how it is done when it is actually required, that way you can see what you can/should do to keep him safe based on this premise.

 

[davesparks]

Is he going to be working on his own in there? If he is then who is going to push the emergency stop for him if he does need it?

 

[telectrix]

you could fit dead man's foot pedals to each piece of equipment. soon as he releases the pressure, the power is cut.

 

[overskilled]

Only time he will be in there, is if I'm there (workshop come garage in my garden space...albeit taking up 45% of the garden lol)