House wiring Part III : Wire size

Wire size

Type of cable	Size (mm)	Best for
	1.5	Lighting point, fan, normal point
	2.5	Plug point
	4	Appliances require more electricity, air conditioners, water heater

Above table only mention wire size commonly use in a normal household. There are other larger wire size in the market but mostly only for industrial usage. Larger size also means higher price and also for higher electricity usage.

For 2.5mm wire, one roll (I think around 100m long) cost around RM50 – RM100 depending on the size and quality. It can be used for both plug point and lighting point but in term of suitability, 1.5 mm is much preferred for lighting and fan point. Why? Most switch box have smaller wire holes if compare to plug point box. When you do some looping, this tiny hole will give you a hard time if you use 2.5 mm wire.

House wiring Part II : Wire color code

Wire	Color
Earth (E)	Green (Standard: Green or Yellow)
Neutral (N)	No colored (White or Black) (Standard: Black or Blue)
Live (L)	Other colored except Green (Standard: Red or Brown)

This is only a general guide for the color code system. One way to know a live wire is by using a test pen.

Carefully touch the open wire with a test pen then touch with one finger at the back of the test pen. If the bulb is illuminate, it is the live wire. The Neutral wire is any other wire except the Green wire because generally, Green wire is the Earth.

Before cut
After cut

For my house, they use green, black and red wire. But for some lamp and fan points there are only green and black wires. In this case, the black wire or sometimes red wires need to be cut. Then use the test pen method to know which one is the Live wire. The other wire will be the Neutral wire.

Note:
Usually, electrical appliance use standard wire color code. The best way to know the wire type is by reading the manual or look for the E, N and L marking.

Some electrical appliance such as fluorescent light and ceiling fan only have Neutral and Live wire. The Earth wire you have to fix it by clamping the tip between the ceiling and the light casing or for fan, screw it to the down rod.

House wiring Part I : Introduction and Cost

Last Sunday, I planned to install a study lamp and also add a couple of wall power plug in my daughter’s room by myself. It’s already been 2 years since I did the house wiring but luckily I still have my unpublished and unfinished blog note left forgotten inside my old dying external hard disk. So, here the blog note (edited for current writing).

---

2 years ago, I moved to a new house. Like other new developed house, the developer provides only basic wiring without any electrical equipment such as ceiling fan and light. With only 2 fan point and only a few power point, the house need a lot of wiring.

To calculate the total damage if I hire an electrician to do the work, I asked 4 electricians to quote their price:

2009 price

	Price	Note
Power Point	RM70 to RM80 per point. (price for conceal wiring)	For each additional power point, need to add RM10 to RM15
Water Heater	RM120	Not includes water heater installation, just the wiring
Air-Cond	RM150
Normal lamp wiring	RM40	This is normal wiring where they just loop from another existing fan or lamp wiring. Add RM5 for light installation.
Ceiling Fan	RM40-RM50	Add RM15 for fan installation. Fan hook cost RM5
Exhaust fan (kitchen)	RM70 with installation

Empty wall

From the quoted price, the total price for complete wiring of my single storey house will be almost RM2,000. This is the total price for several new power plugs, new fan and light points and also installing the electrical equipments. The price doesn't include electrical equipment.

So, with very tight budget I decided to do most of the wiring with a guide from a friendly electrician.

Above price list doesn't include down light point because I don't plan to install any. But from my survey, the price per point is around RM35 - RM50 not include hole drilling and fitting light. Mostly add RM5 to fit the light bulb.

Before we proceed, please note that:

1. This is only for information purpose. I am not a certified electrician so seek your respected electrician for any electrical work. I done all the wiring with a guide from an electrician.
   
2. I don't know the exact term for certain items, so I use which ever I think best suit based on my understanding.
   
3. Please cut off the electricity at the Circuit Breaker (CB) in the Breaker Box before you do any wiring.
4. This is only applicable for single phase not 3-phase wiring which I don't have any clue about it.