30mA still got chance to save life as the backup (2nd level) protection.
10mA should be the primary protection.

Anything above 50mA building is fire protected but lifes are confirmsure NOT protected. As >50mA @ 230VAC really direct to Nirvana, do not pass go..

This post has been edited by ceo684: May 3 2021, 11:20 PM


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Hey there, how was the water heater? Was the pump good enough for rain shower? Thanks!

The pump is alright, not the most powerful but it does the job. I would say that it is sufficient for the rain shower.

Thanks a bunch Selene, really great info for consideration there.

Thank you =)

Guys, how do I know water pressure is good enough for rain shower? Should I get pump to be safe? I'm staying in condo, 8th floor (total 11 floors)

Connect a device known as a hose to the tap.
Turn tap max flow.
Use a thumb to try to stop the water flow.
If its impossible to totally shut off the water w your thumb pressing on the end of the hose (not stuffing the finger inside the hose ya) then your water pressure is not bad.
If it can be stopped easily.. then water pressure is not that good.

I heard from salesperson that Sharp and Rinnai don't make their own instant water heaters, but they OEM from the same Malaysian manufacturers that produce CENTON and ALPHA. Hence cost wise, manufacturers' brands should be more affordable compared to OEM brands.


As far as I am aware of, most Malaysian instant water heater manufacturers like CENTON ALPHA JOVEN all using RCD.

Well that is the believe.
You can see sharp brand model pricing. The other day online sales, models with motor cost less than RM400. Nowadays, you can get good deals online on sales days.

Yes just wait for the monthly sales day on online shopping platforms. Usually they will have better pricing during that day.

Newbie question here. How do I know what size of cable for my WH? To check whether is it 1.5/2.5/4 mm2? Is it written on the cable or I have to measure? And the size is actually referring to which? The pvc or the copper inside?

And let's say it's 2.5mm2, does it mean all live, neutral and earth also 2.5?

2.5mmsq refers to the surface area of the copper/conductor.

all the size of the conductor need to be the same for the appliance

I see. Thanks. So how do I know which cable being used for my WH?

And lets say if I wanted to change from 2.5 mm2 to 4 to support higher kW WH, does it mean have to rewire from the toilet all the way to the DB? Will it be very expensive? Since now copper price is expensive and also I think hacking has to be done? Anyone know roughly how much for this?

yes.

Cables come in standard size for the most part.
The CSA (cross sectional area) is calculated from "one strand diameter" x "total nos of strands".

We'll assume ur talking about the solid stranded (stiff cable) not flexicord (the soft n flexible stuff used in appliances/extension cord).

2.5mm² is made of 0.67mm dia per strand x 7 strands.
4.0mm² is made up of 0.85mm dia per strand x 7 strands.

If its labelled on the cable, u can read the size from the cable.

If its not clearly labelled, still can cross check:
Using either a micrometer or vernier caliper to measure a strand, roughly u shud get the 0.67 value if 2.5mm² cable. Plus minus a little maybe 0.65 or 0.68, but if its grossly smaller like 0.5 on every strand of a supposedly 2.5mm² cable, then u know the cable is elcheapo substandard cable.

Weighing cables is inaccurate as the total weight also contain the insulation. Some substandard cable their insulation made thicker and copper made thinner, plastic is cheap ma.

4mm top tier cables go for ~RM180-185/100m roll nowadays. Was RM136 in March. Top tier e.g. Mega Kabel, Caramay, or MCMA cartel members.
You will need LNE (3 rolls).
Loose cut only worth if its short distance.. like below 15-20meter otherwise the loose cut premium is also expensive (can be 50-60% or more) depending on where you source em.

Yes you need to rewire from DB for the most part.
Specifically "DB to WH switch, then switch to WH" for L & N. And DB direct flight to the WH (unbroken earth).

Copper went up ~1st Apr, luckily manage to secure full roll for my needs.
As for the hacking.. at a very minimum (starting from WH) you need to hack the line out from WH up to the ceiling. then horizontal run from there to the DB box ceiling part. Then drop down into DB box. (ending at DB). Ask the electrician don't hangman (cut the wire ends so tight in the DB that you cannot move the MCB later on).. can pusing pusing the extra length ("extra tolerance") around the side of the DB box so that next time want to relocate/replace DB box life is easier... if hangman "cut exactly" really challenging to fit everything in place in future when everything else also 0 tolerance. Since the wire also already paid for and they will have no use for that few inches or 1 feet extra..but leaving "a bit of slack for the next guy" really helps.

It may be easier if you have plaster ceiling so only two main parts (start and end) to conceal, and minor hole to pass the cable thru beams or walls as necessary.
Concealing cost money because of the hacking. There is no harm in installing exposed PVC pipe conduit first, if money is a concern.. aesthetic wise when financially comfortable can conceal later.

This post has been edited by ceo684: May 12 2021, 09:20 PM


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Thanks! Welp, I guess I better stick to <4kW wh to save cost haha

A typical 3kW-class heater will work perfectly fine for normal shower in urban area.

If you're in highlands where its abnormally cold then only use 4.8kW type.

any recommendations for water heater with DC pump priced around rm450-600? I wanted the panasonic DH-3NDP1 earlier but comments in this thread mostly give bad reviews.

Prefer a slim and stylish metallic color.

Using the dh-3ndp1 for weeks now, so far so good just there's little noise when pump running and no control on pump power.
Compare with my sis alpha smart revo her heater definitely better, but you pay for the price.

I'm using this Toshiba Instant Electric Water Heater with Pump TSB-DSK38ES3MB. Comes with a sleek design, dc pump, been using it for 2 months so far so good.

no control on pump power means that the water pressure is too strong and cant be adjusted lower? actually my condo i feel the water pressure is good, just feel wasted if i get a normal heater and turns out it cant work.

smart revo almost rm1k

thanks, this is around rm450 right?