240 hook up advice please

[dandywarhol]

I've a 1200 watt invertor fitted to my leisure battery via a 12v. heavy duty tee handle type isolator switch. A 240 volt cable feeds a double 240 socket in the van from the invertor.

I'd like to wire in a 240v hook up without the ZIG malarky.

If I was to fit a hookup cable into the van and wire it into the 240 double socket would that cause any problems with the invertor?

Cheers

[Simon Jones]

So would you effectively be putting to 240 into the output of the invertor by virue of that output being where your hookup comes in? I personally wouldn't risk it especially on what must be a fairly expensive unit. I think this may have been covered before & one solution is to use a relay which when powered by the 240v of the hookup, isolates the output of the invertor. Imagine the mess if somehow the invertor was switched on whilst also being connected vai hookup.

[Aethelric]

Yes it would cause a problem Dandy. It would be quite spectacular. You don't want the mains squirting up the output of you inverter even when its switched off. Best to fit a changeover switch or a plug and socket arrangement so that its impossible for the mains and the inverter to get connected together. Don't forget your RCD.

Dave

[dandywarhol]

Thanks Simon/Dave - fair point about the 2 inputs fighting. I'll search for some info on a switching relay rather than trust the isolator.

[Aethelric]

Personally, I'd keep it simpler than a relay. You have a manual switch on your inverter anyway, why not just add a manual changeover switch so your socket is either fed from the mains or the inverter. The worst that would happen is that you could accidently leave your inverter running while on mains. But it wouldn't be feeding anything. If you fitted a neon on the inverter output it would even let you know. Switch both wires though. Mains is 240V and 0V. Inverters are usually +120 and -120.

[apole]

Another solution is to have 2 plugs, one fed from the inverter and the other from the hook up.

[pippin]

From the nature of your enquiry, I think it would be very much in the interests of safety that you employ the services of a specialist electrician.

There is no simple method of achieving what you have described.

I am desperately trying to be tactful here, but I would rather offend you than see you or yours electrocuted or burned in a fire.

Incidentally, why are you fitting such a powerful inverter?

[haydn callow]

apole.....spot on. foolproof and simple.....what I have always done on my boats

[pippin]

apole - do you mean two plugs or two sockets?

The difference is crucial.

[haydn callow]

One plug.....two sockets....thats what I use.

[Aethelric]

Me too, one socket from the inverter and another from the hook up.

[dandywarhol]

From the nature of your enquiry, I think it would be very much in the interests of safety that you employ the services of a specialist electrician.

There is no simple method of achieving what you have described.

I am desperately trying to be tactful here, but I would rather offend you than see you or yours electrocuted or burned in a fire.

Incidentally, why are you fitting such a powerful inverter?

I've had it in for 2 years now Pippin - it's one I picked up fairly cheaply and I intended to do the occasional microwave meals. It's mounted on top of the dashboard cross tube to act as a heatsink.
In reality I rarely use the 700W microwave (1100W rating) but it will handle a hairdryer etc - I only need to grow some more hair to use it..........

I take your point about using a profesional - but I think I'll go down the double pole switch route as suggested by Dave - can't go wrong that way - or fry the other half as she drys her hair

[pippin]

Ah yes, I remember the pictures now.

If it is a double-pole switch (DPCO) please ensure that all contacts are break before make.
There are also rules on contact separation, not that I know the details off-hand.

In houses that have a standby generator the switch for changing between it and mains supply are usually massive things.

[Aethelric]

It reminds me of when I was trying to explain the old fashioned uninsulated knife switched to ny wife. After a while, she realised what I meant and said "Oh I know, like the ones on Star Treck".
Well they were more photogenic.