Inverter in a garage

[petearm]

Dear Forum,

I have a detached garage from my flat. I wanted mains for lighting but the freeholder wouldn't let me run a cable to it and so I've put a solar panel on the roof which charges a couple of car batteries and I run some low voltage LED lights from this. Everything has been working well but now I want some mains power for things like a radio, occasional use of small tools etc.

I bought a 1000W silverline inverter which is normally used for running appliances from a car. The device has a metal case and a "grounding point" for connection to the vehicle chassis, see following link for manual:

http://www.silverlinetools.com/media/manuals/282572_Z1MANPRO1.PDF

My assumption is that the safest thing is not to earth the inverter. What is best practice?

 

[matt1e]

no don't earth it, connect it directly to the battery and plug what ever you are using into it (don't use it to provide power to any sort of fixed wiring)

Matt

 

[ericmark]

For using one item there is no real need to bond. Once you use more than one item then you have to think about bonding.

To earth or bond is a way to ensure if there are multi faults then some automatic disconnection device will work.

The idea is if a standard lamp body became live to one of the phases and a drill body became live to the other phase then a fuse will blow or MCB trip rather than you being able to touch both parts and get a shock.

However by bonding or earthing you make it so touching the standard lamp body and any earthed item would mean you get a shock. So in bathrooms with shaver sockets for example we don't have an earth connected to the output. With no earth it is in fact safer.

So if you were to wire in a radial circuit around the garage with many sockets using many items then you would need an earth. But used as is you don't.

I have used a simulated sine wave inverter and one does have to be careful as some items do not like it. The only washing machine we could use was a LG. All others would not work with a simulated sine wave. It was bigger than yours at 3kW with 6kW peak. Cable sizes were another problem we used an isolator and three 160Ah batteries with twin 25 mm feed cables.

You are looking at around 100A for yours and that does need some hefty cables.