Thread: Switching/Splitting/Diverting 15amp Power

Is there anything wrong with going the simple way and unplugging/replugging at the extension cord socket, apart from the fact that it is not sophisticated?

Technically, a 15A outlet has to be on a dedicated rather than shared circuit, i.e. it has it's own dedicated fixed cable from the circuit breaker to the outlet, rather than a cable that daisy chains around a number of outlets as is permissible with 10A circuits. Going directly to an outlet, then via a short, adequately rated extension cord is not uncommon and acceptable practice, but I doubt that you locate a commercially available device that is portable and will power one 15A outlet while isolating another, and allow a simple changeover switch to select the powered and isolated outlets. There is simply not a large enough market to cover the cost of having such a device type approved by the authorities.

That means that you either have to go it alone and make something yourself, or have someone make it for you. It is possible to do fairly simply with a pair of outlets, a decent switch, a plug and cable, and some form of insulated housing.

HPM used to supply a double 15A switched outlet for installations where there was a need for two 15A devices operating together, but one of these would still require a selector switch in your situation to ensure that you could not have both units operating together and overloading the inhouse wiring that the sparky will install.

Originally Posted by malb

Is there anything wrong with going the simple way and unplugging/replugging at the extension cord socket, apart from the fact that it is not sophisticated?

No, certainly not. It's just a bit of a hassle and it results in me having a "floating" cord around my workspace instead of cords which are all tidy and in their respective locations along the wall or ceiling. It's more of a tidiness concern than anything.

You can get 2 or 4 outlet 15 amp Powerboards with inbuilt breakers.
Just plug both machines in and only use one at a time, if you do use both at the same time and draw more than 15 amps then the breaker in the Powerboard will trip.

i have the same situation. one 15amp GPO which is actually outside the house on upper level (supposed to be for a air-conditioner). So i run a 10meter 2.5^2mm lead down into the garage. plug that into one of these
http://www.bunnings.com.au/hpm-15amp...entre_p4420182
and then connect the panel saw directly into this and run another 10meter 2.5^2mm to my combo jointer/planer.
I am aware of voltage drop issues, hasn't caused a problem yet and probably will not.

you dont need to flick a switch/toggle from one machine or the other. they all have power supplied to them. but only have one machine turned on at any one time. I turned on the panelsaw (3hp) to make a quick cut while the thicknesser (3hp) was running once. the saw started, but I could it hear it struggling.

I turn off the power box each evening using its inbuilt safety switches, so technically there is only one live extension lead inside the garage throughout the evenings and i dont see any harm in that unless it sits in a pool of water...

Originally Posted by Kuffy

i have the same situation. one 15amp GPO which is actually outside the house on upper level (supposed to be for a air-conditioner). So i run a 10meter 2.5^2mm lead down into the garage. plug that into one of these
http://www.bunnings.com.au/hpm-15amp...entre_p4420182
and then connect the panel saw directly into this and run another 10meter 2.5^2mm to my combo jointer/planer.
I am aware of voltage drop issues, hasn't caused a problem yet and probably will not.

you dont need to flick a switch/toggle from one machine or the other. they all have power supplied to them. but only have one machine turned on at any one time. I turned on the panelsaw (3hp) to make a quick cut while the thicknesser (3hp) was running once. the saw started, but I could it hear it struggling.

I turn off the power box each evening using its inbuilt safety switches, so technically there is only one live extension lead inside the garage throughout the evenings and i dont see any harm in that unless it sits in a pool of water...

Ah, perfect. That's what I need. A bit pricey... I might see how things go with the swapping scenario for a while and then make the purchase down the road a bit.

Nonetheless, great to know that it's just a trip to the BGS away!

Cheers,
Luke

Originally Posted by Luke Maddux

I have one 15amp machine now and I've all but decided to get a second one.

Dont forget - you need a 15 amp dust collector as well or BobL will come and put a curse on your workshop.

Cheers

Doug

Originally Posted by malb

HPM used to supply a double 15A switched outlet for installations where there was a need for two 15A devices operating together, but one of these would still require a selector switch in your situation to ensure that you could not have both units operating together and overloading the inhouse wiring that the sparky will install.

Bunnings have these
http://www.bunnings.com.au/deta-15a-...oint-_p4430422

I have 3, 15A circuits each going back to their own CB in my shed and each have s double 15A GPO on them.

I have them set up so that the machines plugged into these are not used at the same time
1) Welder/plasma cutter and WW DC are plugged into one. My wedding booth extractor runs of a 10A circuit.
2) Compressor and spare (test circuit)
3) Bandsaw and Table saw

Oh yeah and there is also these at Masters.
https://www.masters.com.au/product/9...owercentre-15a.

Originally Posted by BobL

Bunnings have these
http://www.bunnings.com.au/deta-15a-...oint-_p4430422

I have 3, 15A circuits each going back to their own CB in my shed and each have s double 15A GPO on them.

I have them set up so that the machines plugged into these are not used at the same time
1) Welder/plasma cutter and WW DC are plugged into one. My wedding booth extractor runs of a 10A circuit.
2) Compressor and spare (test circuit)
3) Bandsaw and Table saw

Oh yeah and there is also these at Masters.
https://www.masters.com.au/product/9...owercentre-15a.

Thanks, Bob. Following your post I sent an email to the electrician who is doing the work. Lo and behold he responds to emails at midnight! Turns out that, although he told me otherwise on the phone, he called his supplier and is actually able to install a double insertion point GPO.

So it looks like I can just buy two extension leads.

Problem solved!

Maybe of interest here:
When I had a 15A GPO installed, it came to light that the regulations consider a 15A double GPO as a "single outlet". So my 15A GPO is a double power point
I have two machines pluggerd in but can only run one at a time or the 20A circuit breaker trips when the second machine starts (of course I tried!).
Since I can only use one machine at a time, it's perfectly legal and perfectly safe....

In your case, the cheapest option my well be to have a double powerpoint installed (effectively the same price as a single one - $15 at Bunnings) and use TWO extension leads. If you happen to be 'careless' and run two machines, you'll not overload the extension cables if your circuit breaker doesn't trip - in other words if yoru machines use just shy of 20A together.
Ask your sparky if that's an option.

Hi Luke
Some good feeback in those posts...

Now couple of things you need to be aware.. and might want to talk to electrician when he comes
By the regulations, 15A will run on 2.5mm cable (dependent on length of the cable run.. etc_) ..Now putting double 15A GPO... that is equivalent of having 2 x single 15A .. So legally electrician must thing of the worse case scenario where end user will connect and use both sockets at the same time and use maximum power.. which is 30Amp.. To cater for that... he must install 4mm cable and put bigger circuit breaker...
In reality if user has only 3HP table saw.. on a 20Amp circuit (minimum for 15Amp socket) there is plenty of grunt left to run lets say 2HP dusty.. or something smaller... Its just regulations that are preventing it as having such setup in a worse case scenario will cause circuit to trip or even damage electrical cable thus electrician will not install it like that..

My recommendation would be to talk to electrician and explain that you would like double 15 Amp GPO on that cable... .. Might need to pay a bit extra as 4mm cable is obviously more expensive than 2.5mm

Ah, perfect. That's what I need. A bit pricey...

If you do decide to use a powerboard the 4 outlet from Arlec is cheaper that the 2 outlet HPM.

http://www.bunnings.com.au/arlec-15a...block_p7050064

With two extension leads if you do turn on too much equipment and trip the breaker you will need to reset the breaker at the switchboard, with the powerboard it will most likely be the breaker on the powerboard that trips.
(this of course is dependent on many factors, breaker ratings, breaker curves, voltage drops etc. The breaker at the switchboard may trip first even with a powerboard).

[QUOTE=Prle77;1890298]Hi Luke
Some good feeback in those posts...

Now couple of things you need to be aware.. and might want to talk to electrician when he comes
By the regulations, 15A will run on 2.5mm cable (dependent on length of the cable run.. etc_) ..Now putting double 15A GPO... that is equivalent of having 2 x single 15A .. So legally electrician must thing of the worse case scenario where end user will connect and use both sockets at the same time and use maximum power.. which is 30Amp.. To cater for that... he must install 4mm cable and put bigger circuit breaker...



Hello Prie77,

According to my reading of the regulations, AS/NZS 3018-2001 has on P62 a TABLE 6.1 labelled GUIDANCE ON THE NUMBER OF POINTS PER FINAL SUBCIRCUIT. Under the heading 15A socket-outlets, a maximum number of 2 outlets may be installed with 2.5mm2 cable and a 20A circuit breaker using installation methods III, IV, and V. Similarly, 3 outlets are permitted using the same installation methods if the cable is 4.0mm2 and with a 25A circuit breaker. The only reference to a single 15A outlet limit is if 2.5mm2 cable is installed using method II (partially surrounded by thermal insulation), which requires a circuit breaker of 16A.

Perhaps this Standard has been updated? I would appreciate if anyone can cite a reference to any changes. Given the information in this table, Luke should be OK and legal with two 15A outlets on the 20A circuit

Chas.

Originally Posted by droog

If you do decide to use a powerboard the 4 outlet from Arlec is cheaper that the 2 outlet HPM.

http://www.bunnings.com.au/arlec-15a...block_p7050064

Those have 4 x 10A outlets, not 4 x 15A outlets!
I was thinking of this one that I have in my shed: http://www.bunnings.com.au/deta-15a-...oint-_p4430422

Originally Posted by jhovel

Those have 4 x 10A outlets, not 4 x 15A outlets!

Thanks, I don't actually have one was only going by the specs, good to know that the specs are wrong if I am looking for one in the future.

• 4 double pole on/off switches with shuttered 15 amp outlets