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Re: BEWARE - why do extension cords melt?

PostPosted: Fri Sep 23, 2016 7:29 am
by coffe addict
Absolutely safety first. It was run past the sparky at work beforehand and was ok'd. But was only to be used as a 10amp cord from then on.

Re: BEWARE - why do extension cords melt?

PostPosted: Fri Sep 23, 2016 8:07 am
by WTDist
If your goin to the trouble to buy 15A leads then cut the ends off for a 10A lead with 15A cord then you would be better buying 2.5mm^2 from bunnings or masters (masters is about 1/2 price) for $2.90 (bunnings price) then get the length you require and put 10A socket+plugs on but they will need to be heavy duty ones to fit the larger cable width. sockets and plugs from Haymens will cost around $20 together but this will be the best way to get thicker cable to the length you want with 10A sockets. ... e_p4430139

buying a 15A lead for a high cost to just cut it up is a waste of time/money, if your buying the sockets/plugs anyway then 2.5mm cable plus sockets/plugs is better. larger cable has less resistance meaning less heat. I never had hot a hot lead doing it this way :handgestures-thumbupleft:

IMO i would not distill with anything less than 2.5mm, to much at risk since we run at high power for hours non stop. just use the thicker cable and do it safe :handgestures-thumbupleft:

Re: BEWARE - why do extension cords melt?

PostPosted: Fri Sep 23, 2016 9:47 am
by Sam.
Pretty sure 2.5mm is standard size for house wiring going to all your normal 10A outlets....

Re: BEWARE - why do extension cords melt?

PostPosted: Fri Sep 23, 2016 10:23 am
by warramungas
I was thinking that as well and scratching my head Sam. You could run a 4 mm cored cable if you wanted to but you cant change your house wiring any bigger. I use the Kmart specials and while they get pretty warm I doubt they'll melt unless I do something stupid. Might be a slight loss of power from radiant heat though. Doubt it would add up to much.
If you were really concerned just buy some tradie 10 amp cables from most hardware stores.

Re: BEWARE - why do extension cords melt?

PostPosted: Fri Sep 23, 2016 10:25 am
by wynnum1
House insulation can also be a problem if you over load the hottest place will be in the wall.

Re: BEWARE - why do extension cords melt?

PostPosted: Fri Sep 23, 2016 10:28 am
by Carbonator
coffe addict wrote:Sam using a 15amp cord on a 10amp circuit can't possibly burn a house down.
As hilzabilly's electrician friend recommended by putting ten amp plugs onto a 15amp cord you have an additional safety barrier not the other way around

In theory and a perfect world, but I know the majority of people will only do the male end

When doing the 15 A lead mod at the male end only, there will be extra thick cable to the device, however, the female end still accepts a 15 A device (I'll keep things simple for the uneducated).

Now you have a 10A outlet with the real possibility of a 15 A device running at full power off it. All should be OK, protection wise, as the 10 A fuse or CB should trip when the rated current is exceeded - in theory!

Now let's look at old protective equipment, like 10 A CBs that might be 1 KA. All of a sudden, you could be in the shit. These old CBs can have a tendency to fuse closed under extreme load - in other words, the contacts inside the CBs weld together because they can't open in time, like how a spot weld works. I will also add, the fusing of CB internals can also happen when too many things are running off that circuit at the one time, even if they are all less than requiring 10 A each and the addition of a boiler element might be enough to push the limit.

Try to run the boiler on the circuit with the least other devices attached to it. Being on it's own circuit, like home wall ACs are, is the best option, or have nothing else at home running at the same time while you cook. With that in mind, one could buy a 30M 15 A lead from Total Tools for about $30, and run the boiler off that and no plug mod need be made.

So if one is to modify a 15A lead for a long run, do both ends and if done correctly, will add extra protection. If one still gets hot plugs when running high current devices, then there is a problem with prongs in the plugs, old and corroded could be the reason.

Going bigger is usually safer with electrics, but make sure the protecting CB is never rated higher than any of the other components in the circuit. It has to be the weakest link to avoid fires.

Re: BEWARE - why do extension cords melt?

PostPosted: Fri Sep 23, 2016 10:39 am
by coffe addict
Good advice.

Re: BEWARE - why do extension cords melt?

PostPosted: Fri Sep 23, 2016 10:50 am
by wynnum1
Circuit breakers probably a good idea to replace before they age and fail friend had problem from using welder.

Re: BEWARE - why do extension cords melt?

PostPosted: Mon Sep 26, 2016 10:16 pm
by Kenster
this is getting unnecessarily complicated...
all garages should(by law) have a 16Amp circuit... simple.
ensure all longish extension chords do not have any coils/kinks, just run them un ravelled.
So, if you hook up your boiler in the garage, ensure you are not drawing more than 16amps.. google will tell you how to work it out... do the math
Do not run a shit load of stuff from an internal(house) powerpoint as it is only (usually) 10amps, and that is where the problems can occur.
A thicker (16A ) lead is better cos it lets more electrons thru, (less resistance) and will not heat up as much... bit like a larger diameter garden hose...the terminals etc (customising) will not affect the current draw.
That is how i work it...

Re: BEWARE - why do extension cords melt?

PostPosted: Wed Sep 28, 2016 11:50 am
by Psykamaholik
Kenster wrote:all garages should(by law) have a 16Amp circuit... simple.

Which standard is that in?

Re: BEWARE - why do extension cords melt?

PostPosted: Wed Sep 28, 2016 12:36 pm
by stilllearning
Psykamaholik wrote:Which standard is that in?

I think that might have been a suggestion rather than a quote? I'd like to think I'm pretty well versed in the BCA/NCC and Australian Standards, and I've never heard of that...

Re: BEWARE - why do extension cords melt?

PostPosted: Wed Sep 28, 2016 12:52 pm
by Psykamaholik
Same, that's why I asked.

Re: BEWARE - why do extension cords melt?

PostPosted: Wed Sep 28, 2016 1:01 pm
by rumdidlydum
Just a reminder of the rules ;-)

MacStill wrote:The team here has decided that an electrical section is overdue & much needed, so we've created a new area for your posting pleasure.


We strongly urge that if you're giving advise on electrical matter you "must" know 100% what you're suggesting is safe, put simply if you dont know then dont advise in this section.. SIMPLE!!

The team here at believes that all electrical work should be done by an authorised & qualified electrician, we strongly advise against DIY electrical period.

If someone disagrees with a post or believes something posted is unsafe, simply click the report button or contact one of the mod/admin team, once this has happened the offending post will be removed without explanation & deemed a safety breech, no PM's, arguments, excuses or justifying actions etc etc will be responded to.

Continued breech's will result in a warning and possibly a suspension given.

We do care about your safety, and so should you :handgestures-thumbupleft:

Re: BEWARE - why do extension cords melt?

PostPosted: Wed Sep 28, 2016 5:15 pm
by hillzabilly
hillzabilly wrote:I used to have two of 10amp by 5mt extension cords with 2000wt elements,they used ta get quite warm as well ,wich was a real worry for me,an electrician friends solution was ta get a 10mt by 15amp extension cord, remove the 15amp plugs then cut it into two 5mt lengths and fit 10amp plugs ,after wich they never got warm or hot again .cheers hillzabilly

Just ta clear up a point ,my extension leads donot have a plug at both ends ,one end is wired directly to the element,so accidently plugging in a 15amp device is impossible, the lead used was heavy duty 15amp ,they are as long as nessasary and no more,price should never be consideration with elecamatricity and safety,I believe the less plugs and joins and cable length you have the less resistance there is wich reduces the chance of the lead overheating ,because thats what a proffessinal told me ,another point he made to me after checking all my shed wireing was that some power points will become fauly with use and abuse,he had a tester wich plugged into the power point and checked load and resistance wich is something I had not even considered looking at,gobbledegook ta me but after 48years I take no stupid risks with my safety or the safety of those wich I care about the most,I have saved more than enough in this hobby not ta be a tightwad.Plus the fact that your insurance company will be less than sympathetic because of the nature of the activity being conducted .And its forum policy ta leave it to the pros as Rum just pointed out ,so I donot think there is anything left to debate.cheers hillzabilly ;-)

Re: BEWARE - why do extension cords melt?

PostPosted: Wed Aug 08, 2018 7:48 pm
by Maximus_Moonshine
Also important to note that where wires are to be connected via compression screws, they should not be soldered (tinned). If the wires heat up due to high current, the solder melts and the connection loosens, causing arcing. Wires connected into screw down sockets should just be twisted gently back into their normal twist (the way they were inside the insulation - this is called the 'lay'of the wire).

Re: BEWARE - why do extension cords melt?

PostPosted: Wed Aug 08, 2018 9:37 pm
by Matt_Pl
Ok as a sparkie (not a very good one) I see a few problems.

>The active terminal on the power controller shows signs of excess current and over heating. potentially a piss poor join.
>The Soldering on the POT is what we call a bird shit solder. The soldering tech hasn't used enough flux and heat and its again a piss poor join.
>The neutral terminal on the rear of the plug back is a hot joint, hence the blackening at the terminal.

From the pictures I cannot tell the size of the cable.

I want to also focus on a couple of posts that have replied to the OP.

Never use a 15 AMP lead on a 10 amp circuit and grind down the earth pin. Its fucking stupid. Simply put, buy quality extension cords. If your walking back from Bunnings after spending $3.90 on a 15 metre extension cord and wonder why it gets hot, give yourself an uppercut.

The earth pin is designed to take fault current from the load (your boiler) back to earth. If it fails your keg which is metal could potentially become live and kill you when you touch it next.

Prior to running your boiler, Inspect your extension cords for nicks, damage or signs of over heating from your previous run. (look in the female end). If in doubt, replace it. You cant see electricity and it will kill you.

If your house is old school and you dont have RCD's buy a 10 amp portable RCD, it could save your life.

For the record:

A 2400 Watt Element will draw around 10 amps. This is typically that circuits limit in a typical household circuit. Therefor if you plug in your 2400 watt element on the same circuit as your kettle and coffee machine and go to make a coffee you will trip your circuit breaker as the circuit breakers are designed to trip at 10 amps. A circuit breaker is designed to trip to protect the cable, not what is connected at the other end of that cable.

2400 Watt or 10 amps should be run in 2.5mm CSA cable, depending on how the cable is ran, or buried or covered in insulation. This is outlined in ASNZ3008.
3600 Watts or 15 Amps requires 4mm 2 CSA cable. This is generally run as a separate circuit to your switchboard and clearly marked as such.

If in doubt, dont use forums or Utube, just call a licenced electrician.



Re: BEWARE - why do extension cords melt?

PostPosted: Wed Aug 08, 2018 9:59 pm
by Sam.
Excellent advice there Matt :clap:

Re: BEWARE - why do extension cords melt?

PostPosted: Wed Aug 08, 2018 10:36 pm
by db1979
Post of the month :handgestures-thumbupleft:

Re: BEWARE - why do extension cords melt?

PostPosted: Thu Aug 09, 2018 11:53 am
by Woods314
I understand that the circuit breaker is there to protect the cable, but how is it that you can plug a 10 amp lead into a 15 amp outlet?

Re: BEWARE - why do extension cords melt?

PostPosted: Thu Aug 09, 2018 1:18 pm
by Matt_Pl
Hi Woods134XX,

A 15Amp plug will allow you to plug in a 10 amp male to a female. Technically the AS/NZ 3000/3008 standards only govern to the power point. Common sense then kicks in.. A 15 AMP cable utilises a larger CSA when compared to a 10 amp extension cable and the 15 amp circuit is designed at a larger CSA then a 10 amp lead this allows for higher current.

The biggest difference is the earth pin and potential fault current in a 15 amp circuit when compared to a 10 amp circuit, hence why the earth pin is larger. It allows more current (which is limited by the circuit protection IE Circuit breaker) at the point of the fault and then returning to earth before the circuit protection disables the electrical potential to ground.

Think of current as water pressure. What you are essentially doing in simple terms is cutting a fire hose, joining it together with garden hose and joining a fire hose to the other end of the garden hose and turning on your higher pressure mains and waiting for water to come out at the other end.

The circuits designed for a reason, anything varing from the original design has a chance to cause excessive heat, fire or a potential of electric shock.

Electricity really isnt worth fucking around with. If anyone's in Darwin and your not a sparky dont guess and follow online advice. Send me a PM and I'll happly talk shit and wire up your elements at the cost of conversation + materials. Its just not worth messing with if you don't know what your doing, If you fuck it up there is a potential to kill the next person who touches your still while your underway.

Sorry for the language, but once again, Just don't do it.