Why only 4 outlets per run of 2.5mm cable?

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moltenfire, May 13, 4:58am
Can anyone explain the rationale behind this new rule. ie only 4 where it used to be 5. Surely the MCB (fuse) sizing would do it's job of protecting the cable no matter how many outlets were supplied?

ryanm2, May 13, 5:15am
Ive never seen any documentation to suggest there is a minimum or maximum. It all comes down to size of cable, hows it run (in batts, outside, in conduit etc all change the current rating) and type of protection.

russ18, May 13, 5:19am
Sounds like another made up rule to me.

ianab, May 13, 5:23am
At some point you can load up the combined outlets beyond what the cable and fuse are rated for.

Heck if I turn on the Jug, Dishwasher, Microwave and Clothes dryer, all on separate outlets, the fuse blows. That's 4 outlets. Having 5 would just make it happen more. No one socket is overloaded, but it's maybe 25 amps though a 20 amp fuse.

Now you might not plan to plug anything more than a cellphone charger in there, but the next resident may have different ideas. Then they will curse the sparky that did this crappy wiring job.

moltenfire, May 13, 5:39am
But surely if the MCB was rated to pop BEFORE the one tps feeding all those 20 sockets even got warm, then it's done it's job and protected the cable?

russ18, May 13, 5:46am
You don't want nuisance tripping, usually a bit of common sense will prevent most problems.
TPS can run very warm.

johotech, May 13, 6:56am
You need to explain what "rule" you think you are talking about or who told you of this "rule".

Because the reality is, there is no rule which limits the number of outlets connected to one cable when it is protected by a circuit breaker.

johotech, May 13, 7:04am
IF you actually have a fuse, not a circuit breaker, then the limit is (or WAS, because fuses aren't allowed to be installed any more) 2 outlets per fuse. If anyone has added more outlets to a circuit that already has 2 outlets and is protected by a fuse, then that wiring is not legal. They should have changed the fuse to a circuit breaker.

tintop, May 13, 7:27am
I think I read of a limit regarding kitchens ? In the diy document? ( which I have lost :( )

johotech, May 13, 7:31am
Ok, they wrote something in ECP51, "electrickery for dummies".

This is what it says in ECP51 about socket outlets:
-Areas such as kitchens and laundries 3 x double socket-outlets per circuit. -Other areas up to 12 double socket-outlets

BUT, those figures are not actually in any standards or regulations.

sandymrph, May 13, 7:52am
Read what you just posted - "those figures are not in any standards or regulations" . they maybe not. So are people just now wiring up willynilly with no regard to how the whole system works ?

johotech, May 13, 7:58am
ECP51 is a code of practice which is a guide for homeowners.

Electricians already know the standards and regulations, and also have common sense not to wire all the kitchen plugs and the laundry plugs on the same circuit - Homeowners attempting electrical work, not so much.

Besides which, any electrical work that homeowners do must be checked by an electrical inspector before it is connected at a switchboard, so any dumb stuff will get pointed out and probably fixed at great expense.

The original poster claimed there was some new "rule" about the number of outlets on a circuit, which there is not.

russ18, May 13, 8:01am
Electrical load and volt drop covers most of what we're talking about.

moltenfire, May 13, 8:04am
The reason I asked is that I added two new circuits using 2.5mm tps, each with 5 outlets in bedrooms. The COC was declined on the basis that only a max of 4 outlets are allowed (?dubious) so after removing the last one and fitting a blank plate, the COC was issued.

davea74, May 13, 8:04am
Electricians know the theory behind what they are doing, so don't need such 'rules of thumb' pointing out.

davea74, May 13, 8:05am
was it an inspector who told you that then?

russ18, May 13, 8:06am
Who was doing the coc?

davea74, May 13, 8:09am
my thoughts exactly.

210sback, May 13, 8:19am
Can put as many as ya want on a circuit,and industry practice will vary.these days when not many plug in heaters are used ya can pump the numbers up.common australian practice is 2 PowerPoint circuits per house so up to 15 odd per circuit keeping kitchen and laundry on seperate circuits.

tintop, May 13, 8:23am
Aha! Thanks Joho.

ryanm2, May 13, 9:09am
This makes very little sense.

moltenfire, May 13, 9:11am
Yes it was an Inspector that I bought in to do the COC.

captaingraham, May 13, 9:54am
Time to find an inspector that knows the rules.

rojill, May 13, 10:01am
Time to modernize and install ring main.

johotech, May 13, 10:04am
Seems that your inspector is working to his own set of rules.

Maybe you could point out to him that even ECP51 says you can install up to 12 sockets per circuit in "other areas".

If he still argues with you, ask him what rule specifically he is declining your 5th outlet.

Have you paid him for the inaccurate advice he has provided you so far?