Adding a new power circuit

[hardy]

I have noticed as a result of using heaters this winter one of the power circuits in my house overloads and trips the 16A circuit breaker. At the moment the power circuit is for one bedroom, laundry and kitchen. I want the laundry on a separate power circuit. My house is a semi attached 2 storey terrace double brick house over 100 years old. I have been told to add the new circuit there are two options.

The first is to terminate the existing GPO in the laundry and rewire the existing GPO with new twin + earth wire 4mm. This new wire would have to travel a distance of approx 20m to reach the switchboard on the other side of the front door in a straight line in a 20mm conduit in the wall through a 300mm x 300mm trench.

The second option is to again terminate the existing GPO in the laundry. Then use the manhole upstairs to access the roof and drop down the new twin + earth wire down the cavity with one end in the laundry and the other end at the switchboard. With this way the both double bricks of the wall in the laundry would be removed to access the wires and rewire the existing GPO.

Could you please advise me which option i should take.

[Ashore]

I would get the quallified lecco whose doing the job to use the second option to remove a few bricks would be a lot cleaner job than trenching

Would it be easier to get the existing wireing replaced with a 20 amp circuit as you could use the existing cables to pull the new cables at each point.

However you go rewireing a place that old if you are not doing a complete reno is a costly and messy PITA,

Rgds

[hardy]

Thanks for your response. Would it be possible to replace the existing 16A circuit breaker with more than a 20A maybe a 32A circuit breaker because the demand on the circuit is high. If a 32A circuit breaker is used should 10mm wire be used to rewire the GPOs? Installing the new 32A circuit breaker and wiring would result in increasing the load on the circuit. Would this increase cause an overload of the existing switchboard? With both options mentioned previously a new switchboard would be installed as the existing one looks like only a 7 pole, and is full?

[Ashore]

Why not put in a new board anyway , once you start getting work done on your wireing etc you will have to put in a earth leakage unit if you haven't already got one and new meters. whats your mains switch one of those old square push to reset types.
As to the cable size you will need for 32amp or the size you need that goes to the meter box thats a job for a quallified lecco .

[hardy]

The mains switch is the ones that you flip on and off manually.

[thatirwinfella]

if you're having to ask so many questions you are obviously not qualified to attempt this job. also, it is illegal to even attempt to do any electrical work on your own home.

have you ever noticed when a house burns down and there is no obvious cause it is attributed to an electrical fault? well, if this does occur to you your insurance company, energysafe, and the last electrician who wired your house will all be trying to point a finger. If you've touched anything in your house your insurance is void and you can have trouble selling your own house [which is a more likely scenario then a house fire, though from the questions....]

As an apprentice electrician who thought he knew a bit to begin with, i now realise how little i know and how much i still have to learn. seriously, get a professional in to do it. I can think of a very cheap alternative to what you've suggested and i'm sure a LICENCED electrician could think of it too. In a house that age, it would be wise to get it rewired regardless, as the demand by most modern kitchens and laundries [as you are experiencing] couldn't have been contemplated by those who designed your house.

for your own sake, get a pro in, or plug the heater into a room on a different circuit.

[Pulse]

Hardy, I have to agree with thatirwinfella, You can't add a circuit without considering the house as a whole eg RCD protection, maximum demand calculations etc.

Adding a new circuit to a house that was wired last year with expansion in mind is one thing but fiddling with old wiring, trying to make it modern on the cheap, is another.

Pay for an electrician, help him do the job or do the chasing for the new circuits and learn.

Cheers
Pulse

[spartan]

I agree with the other other guy (thatirwinfella), except about the bit about your insurance being void.....we debated this in other threads....

<gets atop the hobby horse>

As I've said in other posts....tell people not to do it 'cause it dangerous and the like...but because of insurance is a mute point.....

What electrical standards do they have in NZ? (AS/NZ 3000) - same as ours, yet you can do a lot of your own electrical work yourself there (majority of home electrical except switchboard work, and adding circuits in fact)....do insurance companies pay claims yes there? yes they do.....

Do insurance companies pay claims when you daisy chain five powerboards, connect a bar heater get tanked and knock it over and then go to sleep.....yes they do....No doubt there are many backyard sparky's who are quite competent to do of a range of electrical work safely (albeit illegally), but the vast majority of them wouldn't dream of touching a switchboard or adding a circuit...

I assume that you are asking the questions so you know what the options are and can consider the pros and cons before calling in an appropriately skilled person...

<gets off hobby horse>

[Pulse]

Well said spartan,

I think withholding knowledge on the basis that someone will harm themselves as a result of that knowledge is paternalistic and at times arrogant.

Surely it is better to give that person the knowledge so they see that the job is hard and then leave the decision up to them....

..knowledge is power...
power is freedom...

Cheers
Pulse

[Barry_White]

Knowing what I know about two story semi-detached houses in Sydney and having seen many of the old switch boards that exist and the chance that half the old wire is rubber insulated and cotton covered and when you disturb it the insulation falls off and run in old metal conduit I would advise as the others have said rewire the house and do it properly with a licenced electrition.

[hardy]

To give everybody some background information i am a computer engineer and have also completed a basic course on electrical wiring and a standards at tafe. I admit I am not a qualified electrician. I don't mean to be rude but the course i did at tafe was so easy compared to my uni so I don't understand why I even have to justify myself. I posted my question expecting some helpful advice or suggestions only to be insulted by most of you especially thatirwinfella. I don't understand what this forum is for if majority of uses refuse to give help and if you do ask a question that instantly means you are not competent. An intelligent person asks questions if they need another point of view to solve a problem and then re-evaluate with the new point of view or suggestion. From my initial question you could tell I have an understanding of the principles of electricity. <?xml:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" /><o></o>
<o> </o>
Pulse before i carry out any electrical work i will do the maximum demand calculations on my circuits using AS3000 which I am familiar and competent with. AS3008 will be used for to select the cable size. I will only attempt the job if I am sure is safe and suitable. Im not stupid and will not cause a fire as if I will follow the requirements of the Standards AS3000 and AS3008 and rewire according to them. I will not touch live wires and will conduct my work with the power off. I will also get an electrician to certify my work before commissioning. I will not be doing it on the cheap and will purchase everything required. It is all about common sense and logic and using the rules and the theory I know. Also my house was rewired about 30 years ago and I do not have rubber insulated wires covered with cotton. <o></o>
<o> </o>
To thatirwinfella you do not have to be a genius to be an electrician and you really should not insult people asking for advice. I learn things quite quickly and I would appreciate you not comparing me to you now or especially when you were an apprentice. I don’t understand why if there was a cheaper and suitable option that I overlookedl why you wouldn’t tell me. I actually doubt that you know of one as you don’t know the demand on the circuit. <o></o>
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Ashore thank you for giving me advice. <o></o>

[Dan]

If a 32A circuit breaker is used should 10mm wire be used to rewire the GPOs?

AS3008 will be used for to select the cable size

[Sturdee]

..... have also completed a basic course on electrical wiring and a standards at tafe. ............... before i carry out any electrical work i will do the maximum demand calculations on my circuits using AS3000 which I am familiar and competent with. AS3008 will be used for to select the cable size. .............. I will also get an electrician to certify my work before commissioning.

If you have done that and know that, then you should also know that you should ask these questions from the electrician that will certify your work.

Also if you had outlined these details in your original question it may have been answered better but it looked like another incompetant home renovator trying to fry themselves.:mad:

I posted my question expecting some helpful advice or suggestions ................I don't understand what this forum is for if majority of uses refuse to give help

You will find, if you bothered to search, that most of us will not help with detailed electrical questions as that would be assisting you to do an illegal act.


Peter.

[boban]

10mm2 wire for GPO's. Somehow I dont think you could stick one wire in the GPO nevertheless 2.

Anyway.

Hardy dont get your knickers in a knot. Most people here are more than willing to help people but when it comes to electricity most are understandably concerned. Unlike plumbing, you dont just get wet, you get dead when it goes wrong.

I too know a fair bit about electrical wiring but also hesitate to give advice here because I too am not qualified. I'm fortunate in that free electrical advice is usually only a telephone call away.

You might find that most GPO's are wired with 2.5mm2 twin and earth with 4mm used on high draw appliances or where long runs are concerned. Your basic course will have taught you how to work out losses over runs. See this post from Pulse http://www.woodworkforums.ubeaut.com...8&postcount=15 in an earlier thread.

You might find the difference in attitude toward you has something to do with the fact that you are an unknown quantity. So as Sturdee says you may just be another incompetent looking for early retirement.

My advice is to stay calm, explain yourself, ignore the advice you consider rude or unhelpful and you will probably find a pretty good bunch of blokes here.

But if you are getting a sparky to certify your work, there is nothing wrong with you doing the grunt work and getting him to terminate the connections. After all that's what the apprentice does from day one.

I would however arrange this before you start the work. He will tell you what wire to use otherwise read this thread and you will get what you need http://www.woodworkforums.ubeaut.com...ad.php?t=25438

Hope that helps

[hardy]

Dan I do agree with what you said about me asking about what cable size to use. The reason i did was because i misplaced my AS3008 and had not performed the maximum demand calculations yet. I realise now that i shouldn't asked that.

Boban when i wrote 10mm i meant i will be using twin + earth 10mm but im not sure if that exists. I will be using AS3008 to find out what i require based on demand. I will also calculate the voltage drop. I agree with you and i was planning on having an electrician inspect the job first and check my proposed design and certify my work before commissioning. Thank you for your message and comments.

Maybe i should have told my background but i didn't think it was necessary. I understand people would not want to give home renovators detailed electrical information as they might not understand the basic principles of electricity.