Inverter earthing

[norseman]

I'm about to install a 12V inverter at home, to provide a back-up power supply for our LPG central heating.
In addition to the positive/negative 12V cable connections on the inverter there is also one for an earth. The manuf. instructions suggest connecting this terminal to a vehicle's chassis/body, but no mention of any procedure when the unit is installed in a domestic dwelling.
If this connection is still a requirement in this situation, would the copper pipe supplying mains water to the boiler's filling loop provide a suitable earth ?

Any qualified advice greatly appreciated.

 

[ericmark]

If the inverter only supplies one item there is not really a problem with IT earthing or lack of it, the problem only arises where multiple items are powered from one power supply.

IT = Insulated from terrestrial nothing to do with computers.

 

[SUNRAY]

If the inverter only supplies one item there is not really a problem with IT earthing or lack of it, the problem only arises where multiple items are powered from one power supply.

IT = Insulated from terrestrial nothing to do with computers.

I helped at a school event where we used several inverters for a sports day, the school insisted each one had to be housed in a plastic tub to isolate it from ground and a plug-in RCD to improve safety. Even their caretaker/electrician didn't understand it could never trip.

 

[norseman]

If the inverter only supplies one item there is not really a problem with IT earthing or lack of it, the problem only arises where multiple items are powered from one power supply. IT = Insulated from terrestrial nothing to do with computers.

Many thanks for that advice. Yes the inverter will only be used to run one item at a time, normally the combi boiler. Should anything else be powered (the internet hub for example) it would be instead of, not in addition to.
We are semi rural & though not prone to the outages we used to suffer I am a belt 'n braces bloke, concerned that with the UK sliding down the slippery slope power providers will be cutting back on the maintenance of it's network in the coming years