Cutting 20mm Gland into metal clad unit

[ScottishGasMan]

Hey guys,

Just wandering what type of drill bit(s) you lot would use if you have metal clad box and you want to cut in a 20mm gland? Have some small 5-10mm hss bits but not seen any as big as 20mm

 

[DaftPunk]

Use either a 20mm HSS hole saw or better still a 20mm hole punch.

 

[ban-all-sheds]

Hole punch, without a shadow of a doubt.

BTW - no knockouts?

 

[ScottishGasMan]

For the metal clad switch fuse, came with one large knockout (40-50mm) top and bottom.

Want to pop 3x 20mm Glands in so the DNO guy can just put the meter tails/earth through them into it when Its all ready to get hooked up.

 

[ScottishGasMan]

And bottom knockout will already be used for 25mm SWA to the CU

 

[flyingsparks]

You can't do that. All the live conductors need to go through the same hole because else you can get Edy currents in the steel.

 

[mfarrow]

You can do that, you just need to cut slits between the holes to prevent the flow of those currents. Blade width will do.

My main concern though is how you will achieve IP4X on the top surface of the enclosure. You either need to use stuffing glands or have the cables come in through the side.

 

[ban-all-sheds]

Or use the bottom knockout for the tails etc, and the top one for the outgoing SWA.

 

[ScottishGasMan]

So are you saying I could use the glands in the side if they were close together and a slit cut between them?

Would love to just stick the swa in top, but its 3 core 25mm and not enough room in meter cupboard to work swa round into top

 

[ban-all-sheds]

So are you saying I could use the glands in the side if they were close together and a slit cut between them?

So are you saying that if you already had a hole punch, and were quite happy that it was a good way to make your holes, you'd not have posted this topic, and would have ended up with one tail per hole?

 

[ScottishGasMan]

Yes.

Hopefully the DNO would have brought it to my attention and not proceeded.

 

[mfarrow]

So are you saying I could use the glands in the side if they were close together and a slit cut between them?

Yes. They don't have to be close together; it's the slit that's important.