Yet another weird one...

All the control wiring on the coating plants used white wires, they were all numbered though but only one end. Wasn’t good when we cut one multicore as we thought it would be quicker to rewire. :(
 
Nabsim said:
All the control wiring on the coating plants used white wires, they were all numbered though but only one end. Wasn’t good when we cut one multicore as we thought it would be quicker to rewire. :(
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Aircraft are all white wires with numbers, in ww2 Boeing used ferrets in the B17 assy line to pull the wires up tubes from point a to point b.
 
TrickyDicky said:
Somehow I seem to specialise in weird ones!
Now I find my Elnagh Marlin has all its cabling polarity reversed!
Brown = negative and blue = positive.
Frequently not important but when it is, its easy not to remember and get it wrong...
But why on earth wouid they do it like that....
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Common 12 volt colour code in continental motorhomes at one time Hymer were the same.
 
trevskoda said:
If ac pos live hot side and neutral are reversed it is dangerous, live must always be on the switched side, yes many ac goods will work but its very dangerous.
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A lot of the cabling/wiring inside an electric cooker has a switched Neutral and not a switched Line.
 
sparrks said:
A lot of the cabling/wiring inside an electric cooker has a switched Neutral and not a switched Line.
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I suppose this reduces the voltage at contact and so contact erosion.
Or is this a misconception?
 
Markd said:
Sargent PSU seems to have a polarity check light.
All you have to us remember to rummage in the cupboard and look at it when you hook up 😀

One gathers that our soon to be ex EU cousins are less fussy about how they wire up mains?
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Not just you
 
Somehow I seem to specialise in weird ones!
Now I find my Elnagh Marlin has all its cabling polarity reversed!
Brown = negative and blue = positive.

when you say “polarity is reversed” are you referring to the AC mains system or the 12v DC system?
on continental mains systems, polarity isn’t an issue.... AC (alternating current) appliances will work whichever way the colour are wired. When switched, they use double-pole switches which isolates both circuits, just the Earth (ground) needs to be correct.
12v DC, it’s not at all uncommon for the -12v to be brown... on some vehicles it’s black.... or white.... +12v can be red, blue or a variety of other colours, depending on it’s function. If everything works ok, then the polarity is NOT the wrong way round.
Refer to the vehicles wiring diagram!
If it’s wired in accordance with that, there is no issue.
 
I have a three pin plug that tells me if I am on the right polarity if you are it will show you three lights if you are on the wrong polarity it will show one or two lights so to make sure you are on the right polarity I have made up a cable to change the brown and blue wires over to do this just swap the live and neutral over this will make sure you are right.
 
colinmd said:
Are you referring to 12v or 230v? If 12v then manufacturers can use what colours they want even if it has the potential to confuse, found that out with GM who used black(or was it black/grey?) as +ve. If it's for 230v, then in many countries they often don't seem to worry about live/neutral colours.
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Positive and negative = dc
Live and neutral = ac
 
Glynno said:
Positive and negative = dc
Live and neutral = ac
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I was edumacated up to ONC in electrical engineering so am well aware of that, however due to OP mentioning brown and blue, and then -ve/+ve he may have mixed up terms, it often pays to double check this on forums.
 
TonyEmm said:
....when you say “polarity is reversed” are you referring to the AC mains system or the 12v DC system?
on continental mains systems, polarity isn’t an issue.... AC (alternating current) appliances will work whichever way the colour are wired. When switched, they use double-pole switches which isolates both circuits, just the Earth (ground) needs to be correct.....
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The thing is, when you are taking your UK made Motorhome to the continent, you are very often also taking your standard UK switches & breakers with you, which are single-pole and thus only isolates just the live - or is it just the neutral? (who knows with continental mains systems ;) )
 
colinmd said:
I was edumacated up to ONC in electrical engineering so am well aware of that, however due to OP mentioning brown and blue, and then -ve/+ve he may have mixed up terms, it often pays to double check this on forums.
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I think it is obvious to anyone that has a German built motorhome that he was talking about his 12v DC system, it would have been better if he confirmed it though 🤔
 
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