Help Me Wire My House

[haveaniceday]

I really like the UPS idea, I am wiring up to it.

Below was a guide that I took from post #6 on this thread, my question is, is there a rule of thumb limit to the amount of Watts to draw off 1.5mm² or 2.5mm² like in the example for the hot water heaters? Throw a few spot lights under the eves and before you know it, there is another 1600w !

List from post #6 below.

Lighting circuits:- Wired in 1.5mm² cable with a 10A breaker.

Outlet circuits:- All wired in 2.5mm² cable with a 20A breaker

Water heaters:- Separate circuits for each, wire in 4mm² on 25A breakers (up to 5.5kW) or 6mm² on 32A breakers (up to 7kW) or 10mm² on 40A breakers (up to 8.8kW).

I also want to have lights on the power poles along the drive way, our "cowboy" sparky says it's ok to strip some insulation off the N & a L 50mm² inbound cable from the meter and run the lights directly off that with a switch at the base of the pole. I call BS. Only positive is the lazy ass sparky saves running a line from a consumer unit after CB's & safety switch, means I cant control the lights from the house & opens up the cables to another spot for corrosion. A little question, the max distance is only about 100m I would be running a small cable, to just a few fluro lights, does voltage drop raise it's ugly head again, or is it so insignicant it is a non issue.

The yellow pvc conduit is going in to be rendered over to the outlets 50cm form the floor, the sparky is insisting that the cables from the satitile dish can go in the same PVC, be it to two outlets next to each other. I don't know but I am concerned. Is it ok ? Will it effect the signal?

Thanks again folks.

Edited December 13, 2011 by haveaniceday

[Crossy]

Below was a guide that I took from post #6 on this thread, my question is, is there a rule of thumb limit to the amount of Watts to draw off 1.5mm² or 2.5mm² like in the example for the hot water heaters? Throw a few spot lights under the eves and before you know it, there is another 1600w !

For 1.5mm² on a 10A breaker limit the load to about 1500 Watts of lighting, the theoretical limit is 2000 Watts so there's a bit of leeway and de-rating if the cable is hidden under the insulation. If you're using CFLs or fluorescents with electronic ballasts (recommended) then that is a LOT of lighting.

If you have a lot of lights split them between more circuits rather then use bigger cable and breakers, then if a breaker goes out you don't lose all the lights.

I also want to have lights on the power poles along the drive way, our "cowboy" sparky says it's ok to strip some insulation off the N & a L 50mm² inbound cable from the meter and run the lights directly off that with a switch at the base of the pole. A little question, the max distance is only about 100m I would be running a small cable, to just a few fluro lights, does voltage drop raise it's ugly head again, or is it so insignicant it is a non issue.

I would fire the sparks unless he does what YOU want, you are after all the customer.

For your street lighting, let's say five 36W CFL street lights or fluoro's, that's about 200W or less than an Amp at 220V. Even 1.5mm² cable is going to drop only 2.6V, worry not. One thing to consider, since you will be running this cable along the poles ensure it is big enough to support its own weight, we don't want to start messing around with catenary wires.

The yellow pvc conduit is going in to be rendered over to the outlets 50cm form the floor, the sparky is insisting that the cables from the satitile dish can go in the same PVC, be it to two outlets next to each other. I don't know but I am concerned. Is it ok ? Will it effect the signal?

NO!! Never run power and data or signal cables in the same containment. Apart from the possibility of interference (and these do exist) there are safety issues. What happens if you have an insulation failure on your power cable (crappy taped joint perhaps) and 220V gets into your satellite or network cable. No problem with a dual outlet but the incoming cables must be separated.

A word of warning regarding the UPS. The one we have has fans which run continuously, these are loud enough to be annoying if they are in a lounge (ours is outside anyway so no issue).

[haveaniceday]

Thanks big time. Looks like the firing squad will be out today.

Question: Is there are ballpark figure as well for 2.5mm² 20A breaker. ??

Just looking at one of the outlets in the kitchen, at max load could pull 3500w with microwave, kettle, rice cooker all going.

Clearly this outlet needs to be its own CB, I was planning 4mm just after a de-rated and a max number for 2.5mm.

Regarding I would need a hell of a lot of lights on a 1.5mm cable to have issues. On some circuits I am going to put sensor spot lights, with 2X200w bulbs each, that's what I was concerned about.

Thanks for the fan tip in the UPS, there i a wait on the "new add" on storage room for foundations to be done, aka crap room. Decided to finish the house first, it will be fully detached form the house and connected by a covered area. I am sure the inlaws will love the fan .

[Crossy]

Question: Is there are ballpark figure as well for 2.5mm² 20A breaker. ??

Just looking at one of the outlets in the kitchen, at max load could pull 3500w with microwave, kettle, rice cooker all going.

Yes, it's wise to have a separate (or even two) circuits to the kitchen plus one for the freezer on its own RCBO.

20A at 220V is about 4400 Watts limiting it to 3000W or so continuous load would be wise. Your load would be OK on a single circuit as most loads are intermittent, even we don't boil the kettle all day despite my being a Brit and ardent tea drinker

Consider having CFL floods rather than 200W+ Halogens, significantly cheaper to run (but more expensive to buy).

[haveaniceday]

Just curious, it seems ok to share a common earth wire for different breakers on the same consumer box for what I can gather. I presume this would save a bit of cabling. Is there a serous risk at the joins of a break and make the situation against what I am trying to do. I will be climbing up and following the wiring, I just want to have a better idea.

It is common in the triple wire cable for the earth to be smaller, I often see though a separate earth in hotels on wall mounted hot water heaters, is that due to lack of aviability of easy to get triple cable or do the high risk stuff like washing machines and wall hot water heaters require a heavier earthing wire?

[Crossy]

It is important to follow good jointing practices if you intend sharing a CPC (ground wire) among several circuits and said CPC needs to be sized with the largest circuit in mind. In reality that means decent wire nuts or Wago terminals and 2.5mm² wire. Although you could probably use 1.5mm² in most cases, you would need to confirm by calculation that the protective device would operate in the required time, using 2.5² pretty well guarantees a safe installation.

Twin and Earth often has a smaller ground conductor, it's done to reduce the cost and in most cases does nothing to affect safety except on very long runs.

The separate grounds you see are invariably a result of not having the requisite T&E available and nothing to do with needing a larger ground.

[haveaniceday]

This comment interest me, as I am out light buying this weekend !!!

Crossy: "2 wire for lighting and 3 wire for power is acceptable, note however that metallic light fittings may be Class-1 and therefore require earthing so a third wire may need to run to some fittings."

In Thailand, are fitting in Global / Home Pro all labeled class 1 if they really are? (My instant gut feeling would be no, as it is related to safety !!!)

I was also going to put in a bunch of counter sunk lights in the ceiling, these are metal, would these need to be earthed? What about one of those "small" chandlers type of lights that have metal 'arms' in them ? How about fluro's, they have metal base that get screwed into the ceiling or wall.

On a different subject, I am going to get a common water pump with a pressure tank, They only appear to be a few hundred watts in the motor, I want to be able to power it form a little genny when the power fails, which is often in wet season, I want a easy, cheap and fool proof system, is the simplest way just to have it going into a out door outlet, use a plug with big heavy prongs on it, and psychically the plug move it to a genny when needed ?

[canuckamuck]

Ok I am back in action here. Crossy I hope you are around.

From my original OP, post #1 I have some more info. Here is my meter, I don't know what numbers are important.

And also to my original list, I should have added two water heaters, and a small aircon, 12,000 btu I think.

What type of consumer unit should I buy? One with an RCB included?

[Daffy D]

Very interesting thread with lots of good information

"canvckamuck" slightly off topic but how did you do the house diagrams in original post?

Was it a program or did you do it all yourself.

Thinking of building an extension and this sort of program would be useful to work out spaces and fixings.

Thanks

:jap:

[canuckamuck]

Very interesting thread with lots of good information

"canvckamuck" slightly off topic but how did you do the house diagrams in original post?

Was it a program or did you do it all yourself.

Thinking of building an extension and this sort of program would be useful to work out spaces and fixings.

Thanks

:jap:

I did that in Google sketchup, it's a free download. There is a bit of a learning curve though.

[Daffy D]

Cheers

[Crossy]

Ok I am back in action here. Crossy I hope you are around.

From my original OP, post #1 I have some more info. Here is my meter, I don't know what numbers are important.

And also to my original list, I should have added two water heaters, and a small aircon, 12,000 btu I think.

What type of consumer unit should I buy? One with an RCB included?

Task 'A', go and talk to PEA and get your supply upgraded to 15/45 (currently 5/15). The 5/15 is good for only about 3kW or so and is really too small for your upgraded home.

A 12,000 BTU A/C will draw about 1.1kW when the compressor is running but it's the water heaters that are the killer, one 3,500 watt heater will run on a 5/15 supply, just.

As to your consumer unit, since this is a small installation let's keep it simple. An 8-10 way unit with an RCBO main switch rated to suit your new supply (63A incoming breaker for a 15/45) would do the trick.

Reading back to your OP, there's an awful lot of stuff to run off your supply including a welder. You really do need to list all the kit you're going to be running and do some sort of ball park maximum demand calculation. That said I'm sure a 15/45 supply will do the business.

[canuckamuck]

Ok I am back in action here. Crossy I hope you are around.

From my original OP, post #1 I have some more info. Here is my meter, I don't know what numbers are important.

And also to my original list, I should have added two water heaters, and a small aircon, 12,000 btu I think.

What type of consumer unit should I buy? One with an RCB included?

Task 'A', go and talk to PEA and get your supply upgraded to 15/45 (currently 5/15). The 5/15 is good for only about 3kW or so and is really too small for your upgraded home.

A 12,000 BTU A/C will draw about 1.1kW when the compressor is running but it's the water heaters that are the killer, one 3,500 watt heater will run on a 5/15 supply, just.

As to your consumer unit, since this is a small installation let's keep it simple. An 8-10 way unit with an RCBO main switch rated to suit your new supply (63A incoming breaker for a 15/45) would do the trick.

Reading back to your OP, there's an awful lot of stuff to run off your supply including a welder. You really do need to list all the kit you're going to be running and do some sort of ball park maximum demand calculation. That said I'm sure a 15/45 supply will do the business.

Thanks Crossy. I actually bought a 10 way RCBO unit, but it is 50A. Is this going to be a problem? what does 50A mean anyhow?

As far as upgrading to 15/45, does that require a new meter? I assume it does. Do they install it?

for stuff running in the shed, it is not a frequent thing, and we don't really use a lot of electricity. The father in law uses the welder, it is a fairly small arc welder. I forgot to note what capacity it is, but it runs on the current supply.

Thanks for all your help so far.

[Crossy]

Thanks Crossy. I actually bought a 10 way RCBO unit, but it is 50A. Is this going to be a problem? what does 50A mean anyhow?

As far as upgrading to 15/45, does that require a new meter? I assume it does. Do they install it?

for stuff running in the shed, it is not a frequent thing, and we don't really use a lot of electricity. The father in law uses the welder, it is a fairly small arc welder. I forgot to note what capacity it is, but it runs on the current supply.

Thanks for all your help so far.

Sounds fine, the 50A is the rating of the incoming breaker, what you have will be fine for a 15/45 supply.

Yes, they will replace the meter, they may want to change the supply cable to the house although from your photos what you have looks to be adequate.

The problem with the supplies here is that there are no supply authority fuses so you can just keep adding loads until the poor meter gives up the ghost. These meters are incredibly robust and good for at least a 200% intermittent overload (45A on a 5/15) but they become less accurate when you overload them and you can bet they don't read low.

[canuckamuck]

Ok, I guess I need a little more advice.

Here is the old hookup.

Top view here

I want to toss it all, but I want to save that kill switch and hook it up before my consumer unit.

I assume the the left blue wire on top is the Live feed or L, and the right side top is the N heading back to the meter.

And I am also assuming that the two blacks emanating from the bottom are also left L and right N. The other wire with the white casing is how someone bodged in a wire for my father in law's welder. It goes from there to a 20 amp breaker and then continues to another building.

To keep the kill switch in line, should I just disconnect the two wires from bottom of the switch and then hook up new wires from there to the new unit?

I would also of course ditch the welder wire and hook it in on a 32A breaker in the new unit.

[Crossy]

Ouch!

Yes the wires entering the top of the knife switch should be the incomers, but it's best to trace them through visually. Use your meter to determine which is live and which neutral (use a big screwdriver in the garden as an earth reference).

With the knife open you should be completely safe to work on your system. Hang a sign on it just in case someone decides to make a cuppa and turns it back on (got that T shirt).

Does the knife have any fuses? If so ensure only the live is fused, a fused neutral can be extremely hazardous.

[canuckamuck]

I haven't opened it to see, I will be back up there on Tuesday. I assume it will be obvious to tell which line is fused.

I didn't understand about the big screwdriver. Can I just follow the wire to the meter and see if it is hooked to an L or N?

One more question, How many lights can I run on a circuit to a 10 amp breaker. My 10 breaker unit came with three 10's and I was thinking about running the house lighting through a couple of them? Just your basic ring florescents and such.

PS: What size wire should I run from the knife switch to the new unit?

Edited January 8, 2012 by canuckamuck

[Crossy]

Inside that cover is space for two fuses, they invariably have fencing wire installed but on the off chance that one is a fuse make sure it's in the live side.

It's difficult to follow a wire if you have several the same colour, and there's no guarantee as to which terminal on the meter is which.

Stick a screwdriver in the ground outside and measure the voltage between it (ground) and your incoming wires, Live will be around 220V Neutral will be a volt or two. It's better than relying on your house ground which may not be connected or could be connected to 'neutral' (which may not be). A bit of red tape around the live tail will serve as a handy reminder.

10A is about 2kW at 220V, a lot of lights unless you have loads of 500W floods.

Use 16mm from the knife to your CU unless you have a 30/100 meter at which point you should upgrade to 25mm.

[canuckamuck]

Thanks again

[haveaniceday]

Crossy Said in Post above :

"Does the knife have any fuses? If so ensure only the live is fused, a fused neutral can be extremely hazardous. "

"Inside that cover is space for two fuses, they invariably have fencing wire installed but on the off chance that one is a fuse make sure it's in the live side."

So you simply mean, Live has rated fuse wife (say 60 Amps) and the N has fence wire or in my case a sexy huge wood nail jammed in there.

Why is it so dangerous, not being silly, just learning?

[Crossy]

So you simply mean, Live has rated fuse wife (say 60 Amps) and the N has fence wire or in my case a sexy huge wood nail jammed in there.

Exactly

Why is it so dangerous, not being silly, just learning?

Fused neutrals (both lines actually fused) used to be common in the UK, they have been illegal for about 50 years now. Incredibly they do still appear, usually in ancient farm buildings that were last re-wired before WW2, standard fix is to replace by a copper link (not a wood nail).

The problem is that if the fuse in the neutral opens then the lights go out (duh) but ALL the wiring even the neutrals becomes live (via any load that happens to be turned on) and lethal!

[haveaniceday]

I have a bunch of 16Amp breakers in the distribution boxes, sparky came back to work, after missing in action, has some 1.5mm cable going into 16Amp breakers, I delibatrly made him do many separate circuits, The 10 Amp ones are full, I really should have got some spare to replace other breakers.

Would a 16A breaker protect a 1.5mm wire??

If not, some of the other lighting circuits are drawing very little energy, I would prefer to combine them on to a 10A breaker, if a 16A breaker will not protect the wiring.

Crossy said on page # one:

Outlet circuits:-

Upstairs.

Downstairs.

Kitchen.

All wired in 2.5mm² cable with a 20A breaker.

Lighting circuits:-

Upstairs.

Downstairs.

Wired in 1.5mm² cable with a 10A breaker.

Water heaters:-

Separate circuits for each, wire in 4mm² on 25A breakers (up to 5.5kW) or 6mm² on 32A breakers (up to 7kW) or 10mm² on 40A breakers (up to 8.8kW).

[Crossy]

Assuming these are not massively long runs then 1.5mm on a 16A will be fine, more so if it's not actually loaded to 16A.

Are these lighting or power circuits?

[haveaniceday]

Lighting, all outlets are 2.5mm longest run about 20m.

Some of them are for the future, well near future actually, when installing lighting, a 16 X 36w lights around the perimeter, some of those will be up to 200 meters long wire, I will worry about buying a new smaller breaker then I think, and just go with the flow for now.

Thanks,

HND

Edited January 16, 2012 by haveaniceday

[Crossy]

Lighting,

all outlets are 2.5mm

Won't be an issue, 16A is more than 3kW of lighting.

Lighting circuits are rarely subject to overload (unless you plug the iron into a light socket) so we just have to ensure that the breaker will open if there's a short.

[haveaniceday]

I have a couple of very quick questions going through my head,

I have 3 circuits & distribution boxes, I have kept the earth wires in the roof, separate for each circuit. Now, what about from each distribution box to he ground stake or stakes?

Can I make probs for my self by having them all going into the same ground stake?

or

Should each one have it's own stake? If so, how ar do they have to be separated?

Now briefly onto lightening strikes, I know there are other threads around, but, due to unforeseen ghost, mass ignorance, lack of education on the subject and complete brutal stubbornness, wifie, the lazy sparky & builder have convinced them selves that we are 100% going to die with air terminals on the roof. I am just giving up I am sad to say.

The roof is made of steel, connected to steel rebar in the concrete columns, it is way to late to get my little fingers onto some of the recessed rebar, I would like to earth the roof at least, I have plenty of insulated 16mm copper. (Thin normal insulated, not that really thick insulation). I would like to attach it to the steel frame, run it out side down the external wall at the back of the house and into the ground. I have read on several sites, that this or similar should be done in two spots, another site I can not find, made it clear this should be done on opposite sides of the house, not sure why though.

what are my considerations here?

Airm to put the roof earth stakes as far away from the house hold electrics grounds as possible I presume, how far is a safe distance? The ground is close to the water table and will be moist all year round, I am getting at, they will be good earths.

Running it down the rendered brick out side wall in its own insulation, does it need to be mounted on ceramic 'supports'? (I had bought many dam_n it for the air terminals !!!) or just in some conduit is ok. The roof earthing stakes, is there any rule of thumb how far would be "fried" in the ground if the house was hit and the energy sent down to the stake? I am just thinking what else I have in the ground like, water pipes, metal hot water pipes, grounds for the house, earth stakes for the water pumps and the ground mounted sat dish.

With this cable running down the out side wall, any problems putting it under concrete that runs around the house with rebar in it, (it may be close to the rebar).

OK Thanks guys.

Why is it necessary to have more than one ground on a lightning protection system?

All lightning protection standards call for a minimum of two downleads and grounds in order to provide a circuit or two-way traveling path to ground. Also, a minimum of two grounds facilitate adhering to the standard requiring "common grounding" with the metal water pipe, electric ground, telephone ground, gas piping as well as bonding to metal parts of the building such as eaves, downspouts, metal exhaust fans, ventilators, etc.

http://www.ipclp.com/print/aud_ho_faq.html

[Crossy]

All your power grounds should be connected together, a single ground stake would be a good way of achieving this.

Shame you're not having air terminals, but such is local 'knowledge' on these subjects

If your roof metalwork is welded to the rebar it's probably already got a pretty good ground via the Ufer effect but adding extra cannot hurt. Add grounds at diagonal corners, keep the runs as straight as possible down to 2m stakes, no need to put it on the ceramic insulators unless you want to feel good.

As to whether to link the LPS (Lightning Protection System) and power grounds, opinion seems divided on this subject, in the UK current practice is that you DO link the two, in India they do NOT, in Malaysia we linked via a bloody expensive device called a TEC (Transient Earth Clamp), all agree however that surge arrestors on the incoming supply are a good idea.

I'm going to have to do some more research on lightning protection in tropical locations, for now I personally would not apply a link and would keep the power and roof grounds a few metres apart, but that advice may be subject to adjustment when I've done a bit more research.

[haveaniceday]

I still have 2 small air cons on 2X2.5mm / 1X1.5mm wire. The longest run is only 15m.

Crossy indicated that a small 13,000BTU air con : "A 13,000 BTU A/C will pull about 6A on run, so no reason why you should not put him on a 20A breaker."

​They are currently on B32A CB's. Is it essential to get B20A Circuit Breakers to protect the 2.5mm wire on the next trip to the big smoke ?

I am assuming the answer is yes, but I remmeber something about putting air cons on a bigger CB for the start up.

Last trip to the big smoke I bought many B16A CB's, do you think they will be fine?

[Crossy]

The only way to be sure if the 16A breakers will be OK is to try them, it all depends how much your A/C actually draws on start and for how long.

The 32A breakers will be fine provided you only have a single A/C on the run, since it is a fixed load there is no requirement to provide overload protection, the breaker just needs to provide short circuit protection. If I get a minute I'll do the sums, but to be honest you should be fine on a 15m run of 2.5/1.5.

[Daffy D]

Crossy Said in Post above :

"Does the knife have any fuses? If so ensure only the live is fused, a fused neutral can be extremely hazardous. "

"Inside that cover is space for two fuses, they invariably have fencing wire installed but on the off chance that one is a fuse make sure it's in the live side."

So you simply mean, Live has rated fuse wife (say 60 Amps) and the N has fence wire or in my case a sexy huge wood nail jammed in there.

Why is it so dangerous, not being silly, just learning?

Me too I'd like to know also.

All the knife fuse boxes I've seen have always had those fuse strip thingies on both the neg and live.