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Electric shocks

I sometimes get an electic shock from my light switches and today from the brass door handle from my front door. I have a 12v system with inverter. Any ideas as to what mightbe wrong?

Asked by: Chris Marriott  | 5.47pm, Sunday 4 November

WW says:

The problem almost certainly is with the earthing of the electrical system. Check that the mains wiring is earthed and the invertor is earthed.
The 12V system will be earthed to the hull usually through the engine mounts, and the 230V wiring must also be earthed to the hull. There is often an earth connection on the invertor, which should be connected to the hull. If you are only using the onboard invertor and not a shore connection there will be no problem with galvanic corrosion from the mains earth.
If you have flexible engine mounts and a rubber coupling between the engine and the prop shaft, it might be that there is no primary earth connection to the hull. The solution in this case is to fit a braided earth strap between the engine and the boat.
If everything appears to be fine, check the connections are good with a meter; but if the wiring is OK, the invertor might be faulty. If at all in doubt consult an electrician.

Rupert Smedley  | 6.28PM, Sunday 4 November

The alternative is that you could just be building up static charge in your body and discharging it to earth, or other metal objects. The fact that you are getting a shocked from, presumably otherwise insulated door handles, may suggest you have charge. Less likely than Rupert suggestion, but a definite possibility and worth considering.

Mark Langley  | 8.39PM, Sunday 4 November

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