Hi All I recently had a meltdown on a 15 amp plug and socket on a power lead, the positive and negative pins just melted the plastic around the pins did not stop working found problem when disconnecting have had this problem before but only when using a 10amp power point
I did have 3 extension leads out 60 meters in total but none of the other plugs were affected
any suggestions what could be problem am about to replace plug and socket
They look like home made jobbies. Buy proper ones, not expensive and you won't burn your van down. They are not positive and negative, they are active (the killer) and return (can still kill), make sure you have earth leakage circuit protection.
-- Edited by rgren2 on Thursday 28th of July 2016 01:02:52 PM
Looking at the photo I am guessing that the leads to the two terminals was incorrectly terminated, hence breaking off. A continual make/break cycle could certainly generate heat.
Dirty terminals, either your plug or the inside of the socket you plugged into.
Poor contact builds up heat and just gets worse and worse.
Doesn't blow the breaker until it shorts out, by then it's probably on fire.
I think the likely reason for this problem is this;
"I did have 3 extension leads out 60 meters in total but none of the other plugs were affected"
Ordinary 15 amp leads are restricted to 25 metres total length to avoid excessive voltage drop at the van end.
If you wish to run power over that distance(60 m) you will need to have a lead made by a licenced electrician and it will need to be a minimum of 4mm squared conductor size. Max length for this conductor size is 65 metres.
Hope that helps
Frank
-- Edited by KFT on Thursday 28th of July 2016 02:37:31 PM
-- Edited by KFT on Thursday 28th of July 2016 02:38:00 PM
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Avagreatday.
Kathy and Frank currently at Home near Quirindi NSW
KFT speaks wisely.Unfortunately "15amp " so called caravan leads bought commercially are just 1.5mm lead with extra insulation to protect the cable inside.Looks and feels heavymust be good??. Unfortunately because of the extra insulation on the exterior it does actually meet the specifications of a "15A" lead. If you want cable that will carry 15A without any problems then use a cable that is 2.5mm readily available at electrical wholesalers and sometimes at Bunnings stores. For the little extra in price and fitted with the appropriate fittings it will relay the current you require quite capably. In the safe situation leads should not be joined.
From a non electricians point of view can I just say that cable size seems irrelevant as the plug terminals have failed. A heavier cable would still use the same plugs.
The male plug was shop brought for a caravan and was a sealed unit this is the one that came apart
I agree that leads sold as 15 amp caravan leads are sometimes only leads with a heavy outer and wire is still to 1.5mm
had to join leads as could not get closer to supply was working on a farm
thanks for all your input
All looked good when I assembled the leads the male plug was still like new had little use as I only usually run one lead the female socket was a home made adapter to change 15 amp to 10 amp plug none of the other plus showed any sign of over heating load was lighting fridge and hot water system would normally run on a 10 amp as I new i was running a long lead on 10 amp power point
Well you are lucky ,the consequences could have been serious, since you were using an illegal non approved adapter
The only things that can cause such localized heating are:
Bad connections from either being loose ,or dirty,including wiring in the terminals
heavy overload .
I would put bad workmanship on the list too
They are not positive and negative, they are active (the killer) and return (can still kill), make sure you have earth leakage circuit protection.
