Control enclosure size

[Neale]

I'd go along with the "it's never big enough" idea. Do a dummy layout of the bits going in there, work out what you need to house them, then go a size or two bigger. Otherwise, wiring the thing is going to be like keyhole surgery. Cable trunking as mentioned above is useful but takes more space (and I wouldn't wire another control cabinet without it) and I used a fair bit of DIN rail for mounting things along with a lot of DIN rail terminals. Also consider using crimp-on cable terminations - the little ferrule things - which are cheap enough from China and make wiring much easier and reliable with less chance of odd stray strands causing shorts.