How do you wire yours?

[blodger]

OK, let me suggest a scenario...

 

You have a 12V table lamp, wired to a round plug. You tire of it, and discard it.

 

Somebody sees the discarded lamp, picks it up, and plugs it in at their pub.

 

Who throws away electrical equipment without salvaging the plugs!

[bottle]

Another vote for 2CV bloke and Steelaway posts.

 

I cannot and will not understand why people insist on bodging when to do it correctly is the best and safest method.

 

I have 12v and 240v sockets on my boat and even an idiot could not plug into the wrong one.

[mayalld]

Eggsacaly -

 

Change them all to the PROPER PLUG AND SOCKET!

Just like caravaners

 

Alex

 

The problem is that the "proper" plug and socket are crap, and not fit for purpose.

[twocvbloke]

The problem is that the "proper" plug and socket are crap, and not fit for purpose.

 

I have the US style 12v socket which is just as tight and secure as a proper US socket (I have them too!), the plugs I haven't any experience of, but when you can get them cheaper from the US, it kind of makes the UK caravan plug look expensive...

 

The slanted pin ones do look like rubbish though, I agree, but if it's okay for plugging in a lamp or something, then it's better than making up some potentially iffy wiring for something that wasn't really made for the purpose...

[Gibbo]

do tell, we like tales of pain and suffering on here...

 

Nothing more than a turn of phrase I'm afraid.

[steelaway]

The problem is that the "proper" plug and socket are crap, and not fit for purpose.

 

 

So what you are saying is that a 240V, 3 pin plug wired up in some spurrious fashion is?

 

 

Alex

[David Schweizer]

Your confident assertion that "there can be no mistakes" ignores the fact that there can be mistakes.

 

What happens when somebody on board decides to take a piece of 12v equipment wired on round pin plugs, and plug it into a round pin socket elsewhere that is wired for 240v?

 

The risk-averse approach says that when presented with an unverified round pin socket, there is a risk that there may be 240vac on the lower right hand pin. In consequence (unless the appliance is capable of handling that 240v) you should not use that pin.

 

If the sockets are wired on earth and neutral, nothing bad is going to happen, EVEN if somebody plugs the wrong thing into the wrong socket.

Sometimes I wonder when you will get your honorary degree in Pedanticism Dave.

 

If anyone "took" any 12 volt equipment from our boat without our consent it would be theft, and if they then plugged it into a 240v supply, the consequences would be their problem. If anyone bought the stolen propererty, that would also be a criminal offence.

 

Whilst one cannot set out to deliberately injure a thief, stealing property which is perfectly safe in it's intended environment and then using it in an unfriendly environment might be considered rough justice.

 

If we were to lend or give any 12volt equiplent to another person, I would either mark the polarity very clearly on the plug, or cut the plug off leaving the borrowwer to wire it as they wished.

Edited January 31, 2011 by David Schweizer

[Gibbo]

Sometimes I wonder when you will get your honorary degree in Pedanticism Dave.

 

Shouldn't that be "Pedantry"

 

[David Schweizer]

Shouldn't that be "Pedantry"

 

It takes one, to.......

 

But, If you have a sufficiently comprehensive dictionary:-

 

Pedanticism :

(1)The character or practices of a pedant, as excessive display of learning.

(2) A slavish attention to rules, details.

Edited January 31, 2011 by David Schweizer

[Gibbo]

It takes one, to.......

 

But, If you have a sufficiently comprehensive dictionary:-

 

Pedanticism :

(1)The character or practices of a pedant, as excessive display of learning.

(2) A slavish attention to rules, details.

 

Which is exactly the same as my dictionary description of pedantry (literally word for word identical).

 

But somehow I think a degree in the subject would a degree in Pedantry. A BA in Pedanticism doesn't sound right. Any more than a BSc in biologism would be right

[Guest]

Which is exactly the same as my dictionary description of pedantry (literally word for word identical).

 

But somehow I think a degree in the subject would a degree in Pedantry. A BA in Pedanticism doesn't sound right. Any more than a BSc in biologism would be right

 

wouldn't that be a Bsc in pedantology though....

[Gibbo]

wouldn't that be a Bsc in pedantology though....

 

Don't be ridiculous, it's an art not a science. Oh hang on, you didn't mean that bit.

[mayalld]

Sometimes I wonder when you will get your honorary degree in Pedanticism Dave.

 

If anyone "took" any 12 volt equipment from our boat without our consent it would be theft, and if they then plugged it into a 240v supply, the consequences would be their problem. If anyone bought the stolen propererty, that would also be a criminal offence.

 

Whilst one cannot set out to deliberately injure a thief, stealing property which is perfectly safe in it's intended environment and then using it in an unfriendly environment might be considered rough justice.

 

If we were to lend or give any 12volt equiplent to another person, I would either mark the polarity very clearly on the plug, or cut the plug off leaving the borrowwer to wire it as they wished.

 

That always assumes that you, or I, are here to ensure safety.

 

The system that you set forth represents a "single bus failure node". It is safe ONLY for as long as you are present to ensure its safety. Should you fall under a bus tonight, then the system becomes inherently unsafe, because whoever deals with the boat may not appreciate the safety implications.

 

In my system, even my abduction by aliens will not make the system unsafe.

 

At the risk of continuing pedanticism;

 

I have outlined a way in which my way of doing things can remove a safety risk (even if it is an unlikely risk). So far, you have not suggested any way in which my system is more dangerous than yours, and given that there is no single accepted way of wiring these plugs, I don't think you can claim standardisation as a reason to wire it your way.

 

Bluntly, is there ANY reason whatsoever, other than "well it just doesn't seem right" to wire it your way?

 

So what you are saying is that a 240V, 3 pin plug wired up in some spurrious fashion is?

 

 

Alex

 

Yes, I am saying that it is.

 

It provides good connectivity without excessive volt drop, presents no safety concerns, and is unlikely to present any difficulties in usage. It is an ideal system.

[Guest]

It is an ideal system.

 

if not a bit on the too bulky side though - if it was being invented these days I doubt it would be so damn big....

[mayalld]

if not a bit on the too bulky side though - if it was being invented these days I doubt it would be so damn big....

 

Yes, if we were designing a system from scratch, rathr than being limited by available connectors, that is very true.

[David Schweizer]

That always assumes that you, or I, are here to ensure safety.

 

The system that you set forth represents a "single bus failure node". It is safe ONLY for as long as you are present to ensure its safety. Should you fall under a bus tonight, then the system becomes inherently unsafe, because whoever deals with the boat may not appreciate the safety implications.

 

In my system, even my abduction by aliens will not make the system unsafe.

 

At the risk of continuing pedanticism;

 

I have outlined a way in which my way of doing things can remove a safety risk (even if it is an unlikely risk). So far, you have not suggested any way in which my system is more dangerous than yours, and given that there is no single accepted way of wiring these plugs, I don't think you can claim standardisation as a reason to wire it your way.

 

Bluntly, is there ANY reason whatsoever, other than "well it just doesn't seem right" to wire it your way?

 

 

 

Yes, I am saying that it is.

 

It provides good connectivity without excessive volt drop, presents no safety concerns, and is unlikely to present any difficulties in usage. It is an ideal system.

Really? So why does Gibbo ( a qualified electonics engineer) say? "If a piece of 230 volt equipment (with one of those old plugs on it) is plugged into the 12 volt system, and positive is on the earth pin (like many people would do it) then the case of the 230 volt equipment has 12 volts on it. If it touches something else that is earthed you've got a popped fuse and some sparks."

[Gibbo]

Here is the problem as I see it.

 

There is no universally accepted standard for 12/24 volt DC power.

 

Therefore we have to use something that was originally designed, and is now accepted as being for, something else.

 

Unfortunately that leaves a problem because most connectors are either crap with very low current capability or just dead flimsy OR they are already used for some other power purpose which leaves the problem of things being plugged into the wrong 'ole.

 

I don't think there is an answer that will satisfy everyone. Whatever solution one person comes up with, someone else will pick holes in.

[steelaway]

That always assumes that you, or I, are here to ensure safety.

 

The system that you set forth represents a "single bus failure node". It is safe ONLY for as long as you are present to ensure its safety. Should you fall under a bus tonight, then the system becomes inherently unsafe, because whoever deals with the boat may not appreciate the safety implications.

 

In my system, even my abduction by aliens will not make the system unsafe.

 

At the risk of continuing pedanticism;

 

I have outlined a way in which my way of doing things can remove a safety risk (even if it is an unlikely risk). So far, you have not suggested any way in which my system is more dangerous than yours, and given that there is no single accepted way of wiring these plugs, I don't think you can claim standardisation as a reason to wire it your way.

 

Bluntly, is there ANY reason whatsoever, other than "well it just doesn't seem right" to wire it your way?

 

 

 

Yes, I am saying that it is.

 

It provides good connectivity without excessive volt drop, presents no safety concerns, and is unlikely to present any difficulties in usage. It is an ideal system.

 

 

Thats OK - Each to their own but I can't see how it 'presents no safety concerns', when recently somebody on here confused them with a 240V socket.

 

Alex

[mayalld]

Really? So why does Gibbo ( a qualified electonics engineer) say? "If a piece of 230 volt equipment (with one of those old plugs on it) is plugged into the 12 volt system, and positive is on the earth pin (like many people would do it) then the case of the 230 volt equipment has 12 volts on it. If it touches something else that is earthed you've got a popped fuse and some sparks."

 

Yes, you have a popped fuse, and a spark.

 

However, that will be the extent of the problem; an inconvenience rather than a safety hazard.

 

Thats OK - Each to their own but I can't see how it 'presents no safety concerns', when recently somebody on here confused them with a 240V socket.

 

Alex

 

It "presents no safety concerns", because by wiring the pins as suggeted (NOT using the live pin in a 12V installation), we ensure that the system is fail safe.

 

Even if somebody does plug it into the wrong socket, nothing dangerous is going to happen.

[alan_fincher]

OK, let me suggest a scenario...

 

You have a 12V table lamp, wired to a round plug. You tire of it, and discard it.

 

Somebody sees the discarded lamp, picks it up, and plugs it in at their pub.

I dont, but if I were throwing any bit of 12 volt equipment away, I would always have the plug off first, as I'm too much of a skin-flint not to.

 

Anyway.....

 

Are people in the habit of picking up table lamps at waste sites to equip pubs with ?

 

Is the onus not on them to take steps to ensure it's safe, if they decide to go down this dodgy route ?

 

What if someone discards a table lamp with a thirteen amp plug on, but has a 12 volt bulb in it ?........

 

Personally I remove a 13 amp plug from anything I take to the tip that I think there is the slightest doubt about, just to stop people taking them and plugging them in.

[alan_fincher]

I have outlined a way in which my way of doing things can remove a safety risk (even if it is an unlikely risk). So far, you have not suggested any way in which my system is more dangerous than yours, and given that there is no single accepted way of wiring these plugs, I don't think you can claim standardisation as a reason to wire it your way.

Dave, whilst yours (and Allan's) suggestion to use the earth and neutral pins will avoid ever putting 240 v AC live into a 12 volt appliance, I don't think you answered the thing about which out of earth and neutral is positive and negative.

 

Do you agree that, unless by chance, you and Allan have come up with the same "standard", that your bus rule still applies. If someone takes something where polarity matters from your boat, and plugs it into Allan's, whilst they may not kill themselves, they will likely bugger that bit of equipment.

 

Isn't the reality that in the (very very) highly unlikely event that a bit of 12 volt electrics gets connected to the mains, that a fuse will blow, and that nothing fatal is likely to happen. For it to possibly get live, you would need something twelve volt where any external metal parts are connected to the positive side, not the negative. Such a piece of equipment would be in trouble if it touched a metal part of your boat anyway, however the plug was wired, and I'd not want it on board for safety reasons. What piece of equipment might conceivably be so wired ?

[blodger]

Dave, whilst yours (and Allan's) suggestion to use the earth and neutral pins will avoid ever putting 240 v AC live into a 12 volt appliance, I don't think you answered the thing about which out of earth and neutral is positive and negative.

 

Do you agree that, unless by chance, you and Allan have come up with the same "standard", that your bus rule still applies. If someone takes something where polarity matters from your boat, and plugs it into Allan's, whilst they may not kill themselves, they will likely bugger that bit of equipment.

 

Isn't the reality that in the (very very) highly unlikely event that a bit of 12 volt electrics gets connected to the mains, that a fuse will blow, and that nothing fatal is likely to happen. For it to possibly get live, you would need something twelve volt where any external metal parts are connected to the positive side, not the negative. Such a piece of equipment would be in trouble if it touched a metal part of your boat anyway, however the plug was wired, and I'd not want it on board for safety reasons. What piece of equipment might conceivably be so wired ?

I think some car radios are/used to be switchable for positve or negative chasis; That's all i can thin off. Can't see that if it was wired up to a round three pin plug someone would try to plug it into the mains though.

[alan_fincher]

Thats OK - Each to their own but I can't see how it 'presents no safety concerns', when recently somebody on here confused them with a 240V socket.

 

Alex

I may have missed that - who did that ?

 

The issue that Bazza had is that 13 Amp square pin sockets were being used for 12 volts on board, as well as for 240 volts.

 

That's an entirely different issue, as it presents obvious on board risks - in fact it's an accident waiting to happen.

 

There's a massive difference between using the same plug and socket type for both voltages, (insane, in my view), and using an almost unused (domestically) plug type for the 12 volts, which has precious little chance of ending up in the wrong hole.

 

Potentially Allan and Dave's solution avoids the miniscule chance of someone taking a 12V appliance from the boat, and trying to put it in a 240V table lamp socket in a pub. But unless they can get everybody agreeing a standard for polarity, as well as which pins to use, it still doesn't make 12 volt equipment portable between any boats that happen to use the 5 amp sockets.

 

I use them because they are reliable and effective, unlike anything else I have tried. I have in front of me now the melted remains of a plug based on the cigarette lighter design, on what was the 12 volt laptop power supply. The dog partially dislodged it, it arced, got very hot, and melted both plug and socket. That will not happen once I replace with a 5 amp 3 pin plug, trust me.

[mayalld]

Dave, whilst yours (and Allan's) suggestion to use the earth and neutral pins will avoid ever putting 240 v AC live into a 12 volt appliance, I don't think you answered the thing about which out of earth and neutral is positive and negative.

 

Do you agree that, unless by chance, you and Allan have come up with the same "standard", that your bus rule still applies. If someone takes something where polarity matters from your boat, and plugs it into Allan's, whilst they may not kill themselves, they will likely bugger that bit of equipment.

 

 

Yes, I would agree that this is the case.

 

However, we have ensured that the only consequence of failing to check conventions is equipment failure, rather than potential injury to people.

 

We have also ensured that such equipment failure will ONLY occur where two boaters both use N/E with different polarity swap equipment. Boaters who adhere to the L/N convention will not damage equipment by swapping it.

 

I may have missed that - who did that ?

 

The issue that Bazza had is that 13 Amp square pin sockets were being used for 12 volts on board, as well as for 240 volts.

 

That's an entirely different issue, as it presents obvious on board risks - in fact it's an accident waiting to happen.

 

 

If you follow the N/E convention, it isn't!

[Dominic M]

I think you overestimate the intelligence of some people.

 

I used to own electronics shops (a bit like Maplin). You would be amazed at how many times we were asked for certain leads that simply would never exist. My favourite request was for (not just on one occasion either)...

 

A "scart to 13amp plug"

 

I am not making this up.

 

Broken finger edit.

Reminds me of the wonderful story about a man who rang the help desk of a major computer manufacturer complaining that his computer had ceased working. When asked if he could check the leads were correctly plugged in to the tower unit he replied, "I can't really tell, it's dark and we're in the middle of a power cut."

 

Apparently the help desk operator then asked if he still had the box the computer came in. When the complainant replied that he had, the operator suggested he put it back in the box and return it to them, as he was obviously too stupid to own a computer. The hapless operator was subsequently sacked for this.