Workshop - 16mm armoured from consumer unit?

[Joe2003]

The physical size doesn't matter, the electrical rating is what matters. Many 50 litre compressors have 3HP motors that will blow a 13A fuse on start-up. What rating are the motors on the CNC?

I am well aware of this.

 

[stillp]

So what are the motor and welder ratings?

 

[Joe2003]

So what are the motor and welder ratings?

Does it matter? They are clearly going to be in excess of the 1hp rule....

 

[stillp]

Does it matter?

They'll be very relevant to the design of the installation.

the 1hp rule

That varies between DNOs. What does yours say?

 

[oldbutnotdead]

Running your workshop from the house CU isn't a brilliant idea for all sorts of reasons- one being if your CU features an RCD and something in the workshop trips that RCD it'll be a real pain strolling 30 metres in the rain back to the house to reset

For your design phase, much better to consider Henley blocks between meter, CU and a new switch fuse (of appropriate rating to protect your bit of armoured cable). Then stick the RCD in the workshop along with your garage CU. This also avoids the chore of trying to terminate 16mm SWA in a flimsy plastic (or metal) box not really designed for the job- nice metal AB below the new switch fuse, SWA gland to nice metal box, cores straight through to switch fuse.