You said: "thanks every 1 i think the crisis is over ive had it plugged in for a short while and the beep has stopped when the engine is running both off and on ehu, so the battery must of been flat, how i dont know its only been parked up about a month, i think i will have to keep an eye on it"
This has all the ear marks of an inverter! Now the battery is up, the inverter is happy BUT that means the inverter is switched on and will continue to take juice from the battery even if not being used.
There will be a switch to turn it off.
Also, it may well mean that one or more of your 240v sockets will be live even when you are not on EHU and could take you by surprise. Do try and find that switch 8O
Patrick