I think the white one is for surface mount. That is why the hole is big. It will need very fine job the place the mounting socket flushed to surface and straight to properly place the switch panel. The black mounting box is a bit smaller and the switch facet will act like bezel to cover the hole.

I just use that white cement plaster from Pye to patch. If you mix it right, it will not shrink .

They sell both pre-mix and powder form in box. Much cheaper in powder form and can store it almost forever . I still have some left from several years ago and it is still not caking

Wireless AP can say that it can connect to more than 50 devices. In fact, you have 254 addresses in same network but in reality if you have streaming data you will notice slow down probably after 6 devices

SOHO wireless router is not design for heavy traffic. It has slow CPU and small buffer. The way to improve this is by having multiple wireless APs connected through a switch and segment your LAN network size

I think the mesh is for different purpose. It is for seamless roaming among wireless AP. So, if the signal from adjacent AP is stronger, the device will switch AP and the load will move to another AP. Using separate AP on different subnet would be more logical for loading purpose. So, using mesh would ease load also but not much on your control like separately configured LANs, I would say.

You cook 24 hrs all week long? Why need 24/7 ventilation

You don't use cooking hob?

The indicated power rating on the fan probably not the motor electrical power usage but mechanical shaft power rating.

I'm not sure if the Sonoff pow is measuring just real power only or both real and reactive power.

This post has been edited by Zot: Jan 18 2018, 09:19 AM

Looks like ozak has explained the reason. I thought the color was some lazy contractor using leftover wire of whatever color

If you know which one goes to which one, why not? You can separate them in DB box. Of course wires are separated by color coding in DB, right?

The main incoming switch will cut off all supply. Additional isolation would be pulling out all phase fuses outside the house at the meter

Yes. Big and bulky switches look scary. Once you start doing and get use to it, you become lazy and careless, like no need to go downstairs to switch MCB off

How would you rewire if the wire is embedded in wall? YOu can rewire in the DB but you will have different phase color in another phase group. Will cause confusion for electrician in future.

I think any ganged switch would have 1 common Live input. So, would not solve the problem

Enlarge the hole for another wall switch wouldn't be hard I think. It will look as nice but will have a look of two separate switch

I think there is a way you solve the problem. I'm refering back to the original wiring that you provided:



As you can see from left to right:

1) Red wire to bulb
2) Red wire L coupled for looping
3) Yellow Wire to bulb
4) Yellow wire L coupled for looping

I use different color to denote different phases (orange more visible than yellow )

So, you just chose to use the Red or Yellow phase. Then connect the Red lamp and Yellow lamp to the switch (L1 and L2 if not mistaken). Then just joint the looping wire (either Red or Yellow) using connector by themselves.

This should work. No need to rewire anything. This is what I meant (not sure if your switch is like this. I didn't have one )



This post has been edited by Zot: Jan 19 2018, 08:22 AM

As far as I know the Neutral line is common to all 3 phases. House wiring is Y connection. So, not sure why you have separate N for different phase.

Your 2nd drawing (after) is like what I mentioned. It should not trip anything. I wonder if you did not mix up the yellow/red wire to the bulb with the L wire. If you did, it will trip the CB.

If the N is common to all phases, then both drawing are basically the same. I'm wondering if you mixed up the looping wire and the wire to the bulb.

Anyway, the CB tripped when you switched on L1 or L2 or either one?

We are not expert and hardly do these thing. So, it will take longer time but good or bad, you have satisfaction doing it because you know you do it as careful as possible.

It is not really badly stripped. When they need to loop bigger wire you need to twist two wires together. The size is normally not double but bigger than two wires diameter. So, the easy way is to remove as many strand to easily fit the connector hole. Therefore, forget about your 2.5mm 4mm wire load

Agreed. If the RCB is in the path, the RCB will trip because it will detect imbalance in the circuit.

In rewiring the N at the bulb, I'm not sure if the N of other phase it available at the lamp point that belong to another phase. The only way probably to change the return N at the DB and that would change phase for a group of lighting points. It also will have one wire with different phase going to another phase. Am I right?

My 10 years old house only have classic ELCB only

This is good reference:

https://www.linkedin.com/pulse/what-differe...elcab-engineers

You need yours to trip once a day?