Thread: 15 amp power source ???

Haven't come across 13 amp GPO's before, are you sure they're not 10amp?

At the risk of being shot down in flames here, they are both the same current the difference is how many power points run off the one circuit. For 15amp rating it is one point per circuit, for 10 amp it is up to 10 points per circuit. You can put in heavier circuit breakers, at work we have 20 amp breakers on a couple of circuits (office work only). There are many on this forum that know what they are talking about on this subject and I am not one of them. However the current available at the socket does alter depending on what is happening through the system.

John

Originally Posted by Jedo_03

Hi there
I
So does that mean I need an expen$ive electrician to come and wire up this supply from the fuse box down into the shed (50 metres. . .)?

What's the difference between the 13 amp source I already have and a 15 amp supply..? (yeah - I know it's 2 amps, but what difference does that make?
Thanks
Jedo

q1 - yes, you need a sparkie, or do the slave labour yourself and save a packet - just get him to check your work and off you go...

q2 - a 15A cct will have a bigger circuit breaker (up to 20 or 25) for starting surge. the wires are higher diameter and wont over heat.

advice - if you dont know whats to do - get a sparkie, no question.

advice 2 - do a search on these forums for "15A" and all will be revealed in the results - this topic has been done heaps...

cheers

Originally Posted by johnc

At the risk of being shot down in flames here, they are both the same current the difference is how many power points run off the one circuit. For 15amp rating it is one point per circuit, for 10 amp it is up to 10 points per circuit. You can put in heavier circuit breakers, at work we have 20 amp breakers on a couple of circuits (office work only). There are many on this forum that know what they are talking about on this subject and I am not one of them. However the current available at the socket does alter depending on what is happening through the system.

John

wrong mate. both same volts - 15A is greater currnt.

count of powerpoints make sweet FA diff.

the breakers are for surge current upon start up - 20A is common on a 10A cct.

second last and last sentance of your reply are dead on.

Hi There
Thanks very much for your responses..
Well first... I'm a POHM - so that explains the 13A bit - just asssumed that the current supply of aussie houses was the same as it was back in dear old Blighty..
Anyways - I did a search "15A" as suggested (thanks) and found these comments: which seem to lean the same way as my question "What difference does the 2 amp gain make?


>>I have the Jet 6" jointer, which has the same 2 h.p. motor. It runs perfectly satisfactorily off a 10 amp supply. In fact, I also run my 3 h.p. jet table-saw off a 10 amp supply with no problems. I would say that, unless you have a 5 h.p. table-saw, or want to run several machines at once, you don't need a 15 amp supply.
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>>What's going to happen? The circuit is fused, the fuse blows or you trip the relay.
I'm not a sparky but I can think. The formula for power is 2 Hp = 1592 watts @ 240 volts = 6.3333 Amps.
Unless the wind up is > 50% (which it may be, but unlikely) 10 amps does the business.
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>>My Jet 8" jointer has been running very happily on a ten amp extension lead since I bought it.
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>>In our rental house's garage, there is only one GPO and I have a mass of leads and powerboards set up. However, I can run a 900mm flouro, a compact bulb flouro, a Jet 10" Supersaw, a 1HP DC and the SCMS all at the same time off a single power point.

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So I'm still very much contemplating just using the existing supply...
Jedo

Originally Posted by Zed

wrong mate. both same volts - 15A is greater currnt.

count of powerpoints make sweet FA diff.

the breakers are for surge current upon start up - 20A is common on a 10A cct.

second last and last sentance of your reply are dead on.

At least on this forum you get to find out when you've made an idiot of yourself, mind you I knew both were 240v obviously screwed up the terminology there.

John

What John says is true. Both use 2.5mm2 cable and both use the same circuit breaker 20 Amp. As John says a 15amp circuit has only one point on it where as a 10amp circuit can have from five to 25 points on it depending on how many 10amp circuits there are in the system. If there is only one circuit you can only have five points on the circuit, if there is more than one circuit all 10 amp points should be distributed evenly across all the circuits and can be up to 25 on each circuit provided you work out the maxmum demand and don't exceed it.

A 15amp point has a larger earth pin on it as does the plug on the machine. If no other machine or appliance is being operated on the circuit you can safely operate the machine without any overload of the circuit. The only thing you have to work out is how to put a 15 amp plug into a 10amp point and you should be able to work that out with a bit of commonsense.

Just one other point if it is a mixed circuit ie Power and lights wired into the one circuit you can only have one 10amp point and 3 light points.

Most correctly rated 3HP Induction Motors used in tablesaws would consume a minimum of around 9-10amps continuous on a 240v circuit when running.

However, on startup. Induction motors have the characteristic of requiring 2-3 times this current or somewhere around 20-30 amps. Thus a 15Amp circuit is required. Yes you might get away with a 10amp circuit. However, when your shed burns down and you're explaining this to your insurance. What do you think they will say.

Originally Posted by GregLee

Most correctly rated 3HP Induction Motors used in tablesaws would consume a minimum of around 9-10amps continuous on a 240v circuit when running.

However, on startup. Induction motors have the characteristic of requiring 2-3 times this current or somewhere around 20-30 amps. Thus a 15Amp circuit is required. Yes you might get away with a 10amp circuit. However, when your shed burns down and you're explaining this to your insurance. What do you think they will say.

As I said Greg there is no difference in a 15 amp circuit to a 10 amp circuit except for the number of points. So if none of the other points are in use on the circuit it would not make any difference to the circuit if the machine is wired for 15 amp use.

My main concern would be the voltage loss with the shed being 50 metres away from the main switch board with current draw from the saw.

When 2.5mm2 cable was first introduced you could use a 30amp circuit breaker with it and then with the issue of the 1983 SAA Rules it was reduced to a 20 amp breaker. A 20amp breaker will sustain a 20amp + startup current with out tripping. A 20 amp wire fuse probably wouldn't unless it was a HRC fuse.

I think that Barry has covered the subject well enough in all his posts.

First, thanks muchly for all your advice.
Thinking through it... well I have an existing 10 amp (NOT 13 amp) supply down to the shed already which runs all of my existing stuff already. So If I arrange for an additional 15 amp supply down the shed to run the TS with, then all will be well.
Easy enough to run 50 metres 3 core 2.5mm cable from the box to the shed and then get a Leccy to connect it up.
Thanks again.
Jedo