From what I’ve noticed, metal surface back boxes only ever seem to have 20mm knock outs. How do you attach 25mm conduit to them? Is there a reducer to allow 25mm to enter the 20mm knock out or do you use some kind of drill bit to enlarge the hole?
I’d rather use 20mm conduit and singles to be honest, but only half the installation will be in the conduit and the rest buried in the wall, so I’m thinking 2 x 2.5mm t&e in 25mm conduit may be the better option. Any thoughts? Thanks.
I’d rather use 20mm conduit and singles to be honest, but only half the installation will be in the conduit and the rest buried in the wall, so I’m thinking 2 x 2.5mm t&e in 25mm conduit may be the better option. Any thoughts? Thanks.