Reverse polarity....

Marmalade

Marmalade

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We often go to Oostende where, for some reason, the polarity on the electrics is reversed. At least my panel always tells me it is.

Everything still works however.

Am I incurring any damage by connecting and using the supply? And should I disable the wind gen while I'm connected or does that make no difference?

I had a crashed battery cell last year and wonder if this might have caused it?
 
Marmalade said:
We often go to Oostende where, for some reason, the polarity on the electrics is reversed. At least my panel always tells me it is.

Everything still works however.

Am I incurring any damage by connecting and using the supply? And should I disable the wind gen while I'm connected or does that make no difference?

I had a crashed battery cell last year and wonder if this might have caused it?
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It refers to the AC mains not the DC circuitry A "polarity reversing" adapter in the shore power connection should solve it if it is just the live and neutral swapped.

Damage not likely Some safety aspects because if live and neutral are swapped switching off appliances with just a single pole switch in what should be the live will in fact leave them still live.
 
'Reversed Polarity' on AC will not cause damage. The UK ( I believe) is about the only Nation which clings to single pole switching for domestic electricity supplies - certainly less safe than the double pole system used in Continental Europe.
Single pole only switches the live wire. Double pole switches live and neutral, and completely isolates a system/appliance when thrown.
 
Easticks28 said:
'Reversed Polarity' on AC will not cause damage. The UK ( I believe) is about the only Nation which clings to single pole switching for domestic electricity supplies - certainly less safe than the double pole system used in Continental Europe.
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Don't you belive it. I had to do some wiring in a Portuguese apartment and it was a nightmare. All single pole switching, but biggest problem was various colours of wire used and no earth to many sockets or ceiling roses. Some 5amp wall mounted switches don't switch lights, they're on power socket circuit!
 
No chance of it having anything to do with your battery. You should be able to reverse the L and N supply without a problem to anything except that most fusing and switching is carried out on the Live leg which would then leave the Neutral leg live and hence the equipment live in most cases. I'm a great believer in isolating transformers if you can afford the cost and weight, the use of one would eradicate the problem entirely, increase safety and stray currents.
 
For peace of mind, I made up a reverse polarity lead, 500mm long with the live and neutral switched on one end to put everything back to 'normal'. Male and female fittings and so it goes in line just before the supply enters the boat inlet. Cost £3 or £4 to make.

Don't forget to mark it up very conspicuously - Reverse polarity!

Chas
 
I discovered today that I've got reversed polarity. So will be delving behind panels over the weekend to sort it.

I knew I shouldn't have taken the tester down to the boat.:(
 
Ostend and Dunkirk will always give reverse polarity, its something to do with how they arrive at 220V, after fitting my reverse polarity lead with no change to the warning light, I stripped down and changed my "reverse polarity" lead twice (because I thought I was going mad - still no change) - then an electrician enlightened me.
 
Reversed or floating

Marsupial said:
Ostend and Dunkirk will always give reverse polarity, its something to do with how they arrive at 220V, after fitting my reverse polarity lead with no change to the warning light, I stripped down and changed my "reverse polarity" lead twice (because I thought I was going mad - still no change) - then an electrician enlightened me.
Click to expand...

I often think it is more to do with the Neutral floating at a higher voltage (relative to earth) than we would experience in UK. This is what gives the warning on the testers. It is quite possible to have a completely floating system (i.e. the old 110 systems were actually 55-0-55 and used a centre tapped transformer).

As said previously, this does have some safety implications, and the answer is either dual pole switches or a 1:1 isolating transformer. Other than that, the effect on your equipment is nil in that it still gets 220 or 230 v across the two wires.
 
Floating

starfire said:
The center tap of the transformer in that case is earthed rather than floating.
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You are quite correct, but the point being made was that it is possible to have a supply where both wires carry a similar high voltage, rather than the norm of a Live and Neutral where the Neutral is expected to be 0v (but rarely is!).
 
Marsupial and Mudshipper could you please enlighten me? I've got a polarity reverser as part of a kit for adapting my UK mains lead for use on the Continent for the caravan which I intend to use on the boat. Are you saying that in Ostend and Dunkirk the polarity tester (I have a plug in type) will always show reverse polarity regardless of whether its the right way, or wrong way and using the reverser?

I'm a bit confused as to why anyone markets these kits if they simply don't do anything,
 
Burnham Bob said:
Marsupial and Mudshipper could you please enlighten me? I've got a polarity reverser as part of a kit for adapting my UK mains lead for use on the Continent for the caravan which I intend to use on the boat. Are you saying that in Ostend and Dunkirk the polarity tester (I have a plug in type) will always show reverse polarity regardless of whether its the right way, or wrong way and using the reverser?

I'm a bit confused as to why anyone markets these kits if they simply don't do anything,
Click to expand...

I don't know about always, but I believe these plug in testers work by looking for voltage on the Live lead (good), and a lack of voltage on the Neutral with reference to Earth (also good), and in a good installation this works quite well.

Under abnormal or fault conditions, it is possible for the neutral voltage to be greater than the threshold of the tester, thus indicating a possible reversal.

Conditions that can give this include a poor reference earth, also Phase load imbalance (you will probably be on one phase out of three), and this effect can be increased by the distance from the main supply point.

This may be why the OP has seen a 'fault' indicated whichever way he has connected his live and neutral, as both wires present a voltage.
 
plug in polarity testers

These types of testers have their place in alerting the user to a potential problem, in this case it appears to be external to the boat, the sensible action would be to contact the marina operator to check it out and unplug until its been checked. There are to my knowledge at least 2 types of these devices both operate differently so interpreting the results at a distance is not that straight forward. Also these devices expect neutral and earth to be referenced to each other as normal UK mains, if the boat in question has an isolating transformer which has not been referenced as above you could get misleading lights displayed. In the UK maintenance and testing of marina installations is required with reports and certification to accepted standards, this also applies to the mains installation on the boat its self. These type of testers wont tell you if neutral and earth are reversed, but if you have an RCD fitted it would trip though, assuming its in working condition!!!
Michael
 
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