Electricity in Greenhouse. "Good Practice" question.

[Vortex]

This summer I intend running electricity to my greenhouse for power and light.

It's about a 35m total cable run from a dedicated breaker on my distribution board and will be 4mm Twin/Earth (inside) and SWA (outside/buried).

It can be a pretty moist/condensing environment so I have already installed some IP65 fittings like this:

first thought was to use MK Masterseal switches and sockets in the greenhouse, with a local master isolation switch like this: is should I separately fuse the sockets/lighting circuits in the greenouse or not? Since the whole installation will effectively be an RCB/MCB protected "spur" is local fusing necessary at all?

Thoughts appreciated.

David

[Andy Hall]

I did a provisioning for the greenhouse last year and used Masterseal components for all the outlets and components.

The power outlets are obvious enough.

The Masterseal range includes a lot more components than TLC carries (or shows on their web site.

used an FCU unit into which I fitted a 3A fuse as a way to protect the lighting parts, but cabling from it at the back rather than through the hole in the front plate.

Also in the range are empty boxes that can be used as junction boxes and a neat job can be made.

I used IP65 fluorescents as you have as well as some low voltage halogen lights which run from an IP65 transformer.

[meow2222]

this:

> Question is should I separately fuse the sockets/lighting circuits in the

One way or another it needs its own fuse & rcd else will be a reliability problem for the house wiring too.

NT

[js.b1]

Out of curiosity, how did you do the internal cabling?

Heavy duty 20mm conduit is tough, but not easily sealed & requires a drain hole at the lowest point. HiTuf & IP68 cable glands seem to make best use of IP56-65 rated sockets/lights/switches (ie, maintain IP rating).

HiTuf may not be as tough as heavy duty conduit. SWA seems either overkill or difficult to install in greenhouses/ sheds.

-- JSB.

[Andy Hall]

I used 20mm plastic conduit with shallow bends for going through 90 degrees. For the obtuse angles, I warmed lengths of conduit and bent it around a slightly undersized curved former. On cooling, it springs back slightly. Joints were made with solvent welding.

conduit runs were arranged to accomodate low points with drain holes.

Probably not, but would probably be adequate unless one is going to swing a spade around.