Thank you for sharing all the useful info. Will share once I have more update.

Generally cables increased price by around 25-30% (since March 2021)
for 2.5mm Mega Kabel/Caramay used to be around 85, now its 120-125
for 4.0mm used to be around 136, now around 163 online

Since your work volume is quite a big sum, there are such things called double sockets that will make end user life easier (just pay the variation few bucks in parts pricing). It will not "overload the cables" at all under normal usage (whole circuit MCB protected). Singles are used for small jobs to earn the few bucks "per point"..if all installed double how to earn (since your job is a big job the contractor should be pound smart and not penny foolish)

This post has been edited by ceo684: May 12 2021, 10:39 PM

Thanks for your professional advice. I will ask for this double sockets.

You are exactly right. To me, when I viewed the initial estimation, I already knew the wire, main switch, DB and even TNB panels are over priced. My brother is building his house too and faster than my phase. In my mind, I have the budget which I am willing to pay. But, I am willing to close one eye as long as the jobs are done professionally based on the data centre quality (which was quoted by the subcon).

But, when I saw the price hike from the original contract rate to the new rates, I was quite disappointed. I made the work easier by having additional DB. Even for my LAN cables, I split into "one floor one switch" so that the electrician does not need to pull the wires from main switch or DB to all locations. Now, since he is charging me by point basis and the unit price is RM 403, I rather let him do it from ground floor to all locations.

Lastly, thank you so much for your efforts to explain in the thread. I do pick up a few points to add into my VO.

Hi CEO684, just a few more questions, I noted that my contractor quoted me two pricing for every single 13amp point I requested:

Wiring 13amp power points using 2 x 2.5 sq.mm PVC cables, earth cable and single gang 13A 3pin switch socket - RM 110 per point
Wiring bare channel using 2 x 1.5 sq.mm PVC cables, earth cable c/w switch - RM 46.00 per point

Is this correct? One power plug needs one set of 2 x 2.5 sq.mm PVC and 2 x 1.5 sq.mm PVC cables? I did google myself, I saw some picture of bare channel. It appears to be those fitting for the traditional light



I feel something is not right. What do you think?

Also about the double socket, you refer to this?



Also feature light like the following picture, if there are three light bulbs, it is considered as wiring of three points and the price is RM 100 x 3. But, I saw in Lazada something can do the same job but cheaper:





Thank you so much for your guidance.

This post has been edited by ongss: May 13 2021, 09:43 PM

Ref. above diagram and also to the sections 3.4-3.5  ST_Guidelines_For_Electrical_Wiring_2008_Edition.pdf ( 427.2k ) Number of downloads: 41
:
13A SSO need a full set 2.5mm² LNE (3-wires) from DB into the socket.
"Looping" (connect from next door existing socket into a nearby new socket) is the radial diagram.

For lighting point, they are cheaper since the wire length is shorter and the cables are thinner at 1.5mm².
Earth is optional if not using those old type fluorescent tube with the magnetic brick choke, and is usually not fitted, but its alright to have it fitted.
Typically lights do not come with earth wire, but for the old fluorescent tube with magnetic brick choke, this choke is like a "transformer" that need to be bonded to earth, while the lamp casing is not required to be earthed. Modern LED tube does not use the old magnetic choke so no requirement under section 7.5.

Usually (in standard 1 light point 1 switch, no staircase switching) it is:
single wire L from DB box to the switch, from switch and end at light point.
single wire N starting from light point and return to DB box.



Bare channel usually refer to the "casing kosong" for tube lights. Casing kosong meaning NO starter and NO choke (since these dinosaurs are not required) - LED tubes do not need the dinosaur parts to work. A bare casing will be able to operate LED tubes perfectly, usually these casing kosong is described as for use with LED-only.



Yes. As per the diagram the only extra effort is that the box hole need to be hacked bigger, and you need the double socket with matching box. Itu sahaja.
Identical wiring effort as per single socket as there's only 3 holes to be wired.



Per my diagram.. technically 3 runs from DB box, able to individually control 3 different bulbs on a 3-gang switch (in any possible permutations of ABC on/off) are considered chargeable as 3 points.
If per your picture one light circuit to control 3 bulbs either ALL on/ALL off i.e. just add two wires to the left and right should not be charged as full price since its "looping" that short piece of wire.

Technically this will be branching out 8 lights from one light point. Something like Xmas lights, 100 little bulbs on a single run, but with the RF controller you can turn on each of those 100 little bulbs individually. However, you still need some short wiring from the central controller to the 8 lights (like spider legs).

This post has been edited by ceo684: May 13 2021, 11:14 PM

Thank you so much for your advice.

I think something is going wrong with this subcon electrician. Light points are quoted as a separate item in the contract and I reconcile the number.

For each 13A power plug, the subcon electrician is charging one bare channel to pair with this. Based on your description, I don't need the bare channel. I must be one of the best water fishes in town.

This post has been edited by ongss: May 13 2021, 11:24 PM

Most welcome

For the feature lights.. basically just branch out 2 more wires from where the 1 point is.
If my understanding is correct you just need the wires sticking out where the light should be unless you're going with the tube lights?
(this pic shows a light point, fan point c/w hook, and doorbell point out the wall) but essentially the core idea is a ready-to-hook-up point.



Sometimes.. if the main con not clear about what's going on, then the subcon may add in all the side dish upgrades which are not needed or totally don't make sense.
Bare channel basically means tube light casing, i.e. http://www.degindustrial.com/page/products...l/vegas-1l.aspx and are definitely not required for the 13A sockets..

This post has been edited by ceo684: May 13 2021, 11:36 PM

Ya, I just need the wires sticking out like your picture and they already charge me the Lighting Points.

I think the subcon thought that I would not check details and raise any enquiry. The main con takes the quotation and add their mark-up for the project management fees. When I asked if I could bring in my own electrician, the main con wants to penalize me for any delay caused by my new electrician. But, for the past 5 months, I have never threatened them for delays despite I have paid a large lump sum.

It is good to have forummers like you to help people to read through the items. Otherwise, a lot of home owners will be slaughtered like water fishes.

You should hire a clerk-of-works ("kerani" local speak) to help you sort out all your questions. They'll help you with specifications for everything, how to do things, and check that things are done properly and using the correct materials onsite. Good investment if you are doing major renovations as the additional cost is not that high. If you are in the Klang Valley I have the contact of someone experienced if you are interested.
PM me for the contact . I know him from my kampung. Charges were reasonable for the work

Your thread is so useful that I revised it again and again.

Then, I realize I forgot to answer you the above questions.

1. Wiring water heater power point using 4mm sq PVC cable in PVC cable, earth cable c/w 20amp switch - RM 288 per unit
2. Garden Lighting points (including gate pillar lights) using 1 x 1.5 sq.mm PVC cable, earth cable and 10 A switches. - RM 279 per unit
3. Wall Lighting Point using 2 x 1.5 sq.mm PVC cable, earth cable and 6A switches. - RM 100 per unit

About air-con installation, install the fans, light bulbs, and etc - I will have separate quotations.

I am currently also studying the ABB T2 SPD as the area my new house is also an area with frequent lightning and rain stomp.

The price I received is very expensive because of main con mark-up. My house is also a semi-d with attic. I spoke to a few electricians past few days. Unit prices depends on the quantities. For a small house with 40 power points or 80 lighting points, the unit price are higher. For a big house with 120 power points and 100 lighting points, the unit prices are lower. My brother is building his 8000 sqft bungalow. His unit price is even lower.

This post has been edited by ongss: May 14 2021, 03:50 PM

For T2 SPD this has specific placement i.e. after mains MCB and before mains RCD 30mA. SPD need overcurrent protection of MCB only.
It also has to be connected to all wires (L1,L2,L3 no issue if placed next to mains MCB; importantly is the N and E returns) as short as possible.

Just to heads up why we need a bit of slack in the DB box wiring (ability to reposition and reconfigure layout) coz stuffing in a 4-module SPD (three phase) will need that room to fit. If everything hangman tight this will be tricky.

OMG, 100x Downlights!?
Usually I will isolate the area and just focus on the number of circuits for the lighting.
Eg, Master Bedroom- 1x Cove Lighting, 3 or 4 circuits for Downlight/Track Lights. Any other lighting will be just looping.
Same goes for power socket and I usually use the 2-gang instead of the 1-gang SSO.

It is also best to use different ELCB/RCCB for power and lighting circuit. For my own DB, I used 3 different RCCB, 1 each for Power/A/Cond (100mA), Lighting (30mA) and my Solar Heater (10mA) for practicality and safety.
Storage tank heater uses 3KW heating element while instant shower heater uses 3.6KW heating element.
In terms of efficiency, nothing beats Solar Heater.

Rule of thumb, cable size is equivalent to 10x of current carrying capacity, eg 2.5mm = 25A.
Unless you are talking about 3HP and above AC, there is no need to go for 4mm cable size.

In the market there are 2 types of DB that either:

1. MCB/Isolator as Main Incoming
2. MCCB as Main Incoming

For better protection and easier wiring go for the option 2 though it costs more initially.
Local brands like Safety/MaxGuard/EPS all have these DB with 2 type of incoming as option.

For the RCCB/RCD selection is this correct? You may have swapped them around.
Lighting is something that is generally low risk as user don't touch often and its out of reach of small kids. 100mA for lighting because back then people used a lot of old flourescent with chokes that often trip high sensitivity RCD, so a medium sensitivity 100mA is allowed.

13A sockets and metal forks and curious kids are high risk and therefore it need 30mA.



Selection of either MCB or MCCB also depending on the available mounting type of the DB box itself.
MCB/MCCB usually only cut the 3P live wire. It does not isolate the neutral.
Hence, MCCB does not perform the role of isolator

Isolator (4P) cut all 3P+N so even if some idiota wire the wrong way down the road and sets the neutral as hot wire when you're working on the DB box, you can be assured the whole house is completely isolated off the grid safely.

100mA for power circuits are usually good as one will not need to worry about nuisance trip. As all power circuits are connected to a single 100mA, there is a build up of leakages. Hence putting a 30mA into the power circuit is too sensitive.
Most lighting especially LEDs are very efficient hence the chances of earth leakages is very minor hence a 30mA is best to protect it. Main point here is should a trip occur in the middle of the night on the power circuit, one would not need to wander around in the dark or relying on torch lights. I also forgotten to mention that I specifically told the electrician to wire my fans to the lighting circuit. In the event the trip in the power circuit cannot be resolve at least I still have my fans running.
MCCB does come in TPN configurations as well. At any given time I will always choose a MCCB over an isolator (costs aside).

Wiring bare channel sounds like just "ready" wires to plug into something (like the picture ceo684 showed)? like tube lighting, right? can also be used for others like e27casing + LED bulb, feature lights?
For itemization from contractor, wouldn't it count as a "lighting point"?

Can use 3 gang socket to save another LNE? Couldn't find much, but found this MK brand socket : 3 gang DP double earth socket


One electrician did recommend the same for my new DB and rewiring, but he mentioned 2 different RCCBs only, 1 for lighting, 1 for everything else

Hi sifu's can anyone guide me on this? Is item no1. the same as: (ongss quotation)

If the electrician mentioned 2 different RCCB, then it is 1 each for Lighting and Power Circuit. If you have Heater (instant/storage/solar) it is best to have an additional RCCB of 10mA.

3-Gang SSO is rare, best to use 2x 2-Gang so it is easier to find in the market.

Guys, I am electrical engineering students but now working on something else. But suffice to say copper is very expensive commodity nowadays. The price is doubled.

My suggestion to you is do whole house continuity test for what you can still use. Copper especially the old one is of very good quality. Nowadays although still sirim, the quality level is greatly vary. The cost would start MYR 300 plus.

So after electrician have check your wiring is okay or not, then you change the distribution board. i believe your house 2 2 storey right, so i think it is cheaper and long term to have second DB upstairs. Also one important thing is to understand how much incoming you need (based on your load) and also purchase as big as possible (well based on your setup) distribution board to go with.

My previous bungalow i do, 1 storey the kitchen area require more space then the front one. Also if you want to use strictly code the cost will add up quickly, also the space DIN rail inside your distribution board.

Yes I agree, in fact i do this at my customer house 2 earth leakage circuit breaker/RCCB 1 using 100mA sensitivity and the other 30mA sensitivity. That would be 2 for each DB. 100mA is what difficult to touch like fan and lighting because whereas 30mA like power points etc. Also do adopt new 10mA for each water heater, best to be safe then sorry. With that if you have 3 bathroom, also with minimum 4mm wire the cost is very high.

you need more info please reply, I can reply to what you need. My priciple is always consultation is free for my client. If meter not touch, i dont think we require to called up TNB personnel, only wiremen will do.

Actually its a different market segment. It is not about saving the pennies but it has to be up to code so that it doesn't need further investigations for the near future.
I am also interested in why a 30mA whole house RCD is NOT doable in 2021.

My question is - What kind of domestic device leak so much >30mA, that a high sensitivity 30mA RCD always nuisance trip? Note: device trip as leaky device, not circuit wiring aka wrongly connecting shared neutral in to dedicated RCD (WH circuits).

If the devices are that leaky then the old kettle or old fridge is likely due for replacement anyway.
Nowadays, lighting also noone really install old magnetic choke flourescent lights - all LED drivers / LED tube.
Factory high bay sodium lights? Noone use this at home.
Old kettle element leaky, is time to replace the device.
Old fridge? I have a 1997 Mitsu still running. Never tripped 30mA.
Old water heater? I have 1997 National that needed direct LNE to 10mA. Never tripped. (Previously shared neutral problem that tripped its own 10mA).Never tripped 30mA when no 10mA/WH unit was fitted.
Old rusted toaster from decades ago?
Old Grundfos B&W TV?
Unapproved questionable devices?
Commercial 3 phase dodol mixer? Welding machine? This is not domestic 230V appliance.

My point is - I can retrofit a medium sensitivity 100mA if needed if there is a need to run dodol mixer at home;
But if everything (based on 2021) works fine on a high sensitivity 30mA RCD (single mains RCD) why are we settling for less protection AND wasting DB box space/customer money to buy 2nd RCD 100mA?

The code say for lighting/fan circuit and WH circuit (as secondary protection) maximum tolerance of up to 100mA, NOT exactly 100mA.
Hence, one top tier 30mA RCD already cover all the ST mandatory requirement.
I personally run 30mA as single mains RCD and do not experience nuisance trips.

This post has been edited by ceo684: May 30 2021, 02:15 AM