Splitting a 30amp Circut?

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iROK

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#136513 29-Nov-2013 18:36

I would like to decommission our F&P Paprika free standing oven.
It is on a dedicated 230volt 30amp circuit with a fixed connection (as wired to the standard in 1969/70).

Once the Oven is removed, can the circuit support 1x 15amp socket & 4x 10amp sockets (with an estimated 6kw in use at peak times)?

This is for two different/separate induction plates, a small toaster oven, a dish washer & a spare hot point for other kitchen use.

I can provide model/power consumption spec's if required.

Thanks in Advance!

DarthKermit

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#943078 29-Nov-2013 18:43

I'm not a sparky, but I think you'd need to have a sub main with circuit breakers rated appropiately for the outlets you mentioned.

This could cost more than just running lighter guage cables from your fuseboard to your kitchen.

Whatifthespacekeyhadneverbeeninvented?

andrewNZ

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#943115 29-Nov-2013 19:37

Short answer is maybe.

I'd suggest getting someone to look. It's not as simple as banging on some fittings, there is probably a lot more work in it than you think. you're more than likely going to need work done in the switchboard to bring the new stuff up to the required standard.

You may be holding a can of worms...

gregmcc

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#943139 29-Nov-2013 20:23

What kind of wiring is there in the house? White plastic TPS or black rubber TRS, if it's white TPS then that shouldn't be a problem as long as you change the size of the fuse at the fuse board end.

Now this is where the fun begins, now that you are changing from a 30amp outlet to a mixture of 10Amp and 15amp outlets you must install a suitiable RCD protection, this means fitting an RCD circuit breaker at your fuse board, now been a fuse board from the 70's your now going to be stuck with upgrading the entire fuse board to a modern distrubition board as modern RCD's will not fit on an old fuse board, and depending on the state of the wiring you may need to get a good portion of the house re-wired.

Basically you are about to open a very large can of worms here, best thing you can do it put the can down and walk away.

richms

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#943149 29-Nov-2013 20:51

do it with a subboard that you put the breakers in. There are horrid surface din breaker enclosures that some sparkys will put onto an old phenolic or whatever the later stuff is fuse board, but chances are there is not enough space on it and it will just end up a mess. I have seen 2 houses which have had the old cooktop replaced with a small breaker panel and a few sockets when a gas cooktop was put in its place.

There is all sorts of things they have to do with earth loop impedance on things to make sure it is compliant as well. Poor sparkys having to have all that compliance to deal with. I am glad I have a good sparky as a relative to deal with all that carry on ;)

Im not sure what the maximum that you can have a circuit with power points on it protected at. I seem to recall 25 or 27A from a previous discussion.

Richard rich.ms

Porboynz

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#944358 2-Dec-2013 20:30

iROK: I would like to decommission our F&P Paprika free standing oven.
It is on a dedicated 230volt 30amp circuit with a fixed connection (as wired to the standard in 1969/70).

Once the Oven is removed, can the circuit support 1x 15amp socket & 4x 10amp sockets (with an estimated 6kw in use at peak times)?

This is for two different/separate induction plates, a small toaster oven, a dish washer & a spare hot point for other kitchen use.

I can provide model/power consumption spec's if required.

Thanks in Advance!

Well you can go from a larger gauge wire to a lighter gauge TPE wire OK, but not the other way around. Therefore the initial 30 amp wiring run probably can be reused (5mm?) The main issue as mentioned is that the proposed power outlets will not be protected by an RCD as oven feeder circuits usually bypass RCD's on fuse boards (assuming they are fitted). The fuse rating will also be incorrect for a HP circuit. I think if you need to ask the question it really does mean you really should get an electrician involved, but its always good to know what you are up for, right? Good luck.

iROK

26 posts

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#944400 2-Dec-2013 21:36

Some interesting replies, thank your for your feedback.
OK, so electricity 101; 230V X 30A = 6.9kW of max power can be consumed on this circuit before overloading & 'blowing' a fuse (wire).
Is that a correct statement?

I know the 30A fuse & holder will need to be fully upgraded to the RCD type as the old fitting is too big, and that's OK.

What I want to know; can the EXISTING 30A rated wire (of whatever gauge they used for this type of over range circuit in 1970) be kept in place?
Why does new wiring have to be installed?

AND if it does, can I have the fittings I desire be installed (1x 15A, 3-4x 10A)

YES I will be getting a SPARKY in, just getting one at a time I can be there too...

andrewNZ

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#944410 2-Dec-2013 21:48

Whether or not the cable can be reused depends on several things including what it is and what shape its in.

Ultimately, it will probably be replaced and you'll likely end up with 2 circuits.

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cyril7

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#944419 2-Dec-2013 22:15

I know the 30A fuse & holder will need to be fully upgraded to the RCD type as the old fitting is too big, and that's OK.

You are confusing MCB and RCD, these are not exactly the same thing, by messing with the switchboard you expose yourself to some serious upgrades to meet standard.

Aside of that the existing cable assuming it was a 4 or 6mm TPS can be retained with a 20A MCB plus any RCD protection and a set of 10A sockets on it, why the 15A though.

Cyril

richms

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#944440 2-Dec-2013 23:16

15A for a decent coffee maker, a deep fryer or an arc welder ;)

Richard rich.ms

webwat

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#955805 21-Dec-2013 13:40

richms: 15A for a decent coffee maker, a deep fryer or an arc welder ;)

Mite need a big aircon on the kitchen bench, or a 3kVA UPS to run the sandwich maker.

Time to find a new industry!

iROK

26 posts

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#955877 21-Dec-2013 15:30

Nahh, just it's just a 2.8kw Induction Hob.

Am waiting for the E.Inspector to sign off on the proposed change(s), which might not happen till next year now.
Apparently Gas BBQ's need inspecting too :-P

I'll have to post a photo when done.

iROK

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#990178 19-Feb-2014 09:53

The BILL finally came in last week... $530 with certification.
Traditional Stove gone & Dishwasher in it's place, 2x Induction units on top & a SMART Oven above.
Photo below