It is brainstorming, not war.

Now you have a sonoff wireless wall switch that need the N line? What was your plan?

The other idea is to incorporate switch to door lock. Once you lock the door from inside the bathroom, the light will switch on. The light will be off once you unlock the door. Well, it is not a good idea to have 240V on the lock because your hand is wet. You can use low voltage to trigger a relay to switch on the light.

I have reservation on wireless control on bathroom light. The reason is why do you need to remotely on and off the bathroom light? Unless you are living alone, you can check from your phone if any light left on and switch the light off You need to be at the bathroom to use it and you do not need to switch on the light 2 minute before reaching bathroom anyway

Do you have tool to do simple wiring, like having ladder to access ceiling wiring? There might be solution on how to use sonoff that require N without pulling N wire. Anyway, there are plenty of touch switch that require no N. In general, the one that can be wirelessly controlled one is just normal remote control (like ceiling fan) that use frequency like 433MHz. If the WiFi module is built in the wall switch, the switch most likely need the N wire because the WiFi need more power. The switch with zigbee module does not require N line mostly, for example the Xiaomi Aqara Light Switch.

I think there not many 20A touch switch out there and I've never seen one that can be wireless controlled. They are just normal touch switch.

If you remotely on or off your light, why you need sensor? You need sensor if you don't want to manually control anything, right? Like you have a camera in bathroom and when it capture you naked, it will switch the light on

You may just want simple sensor that detect the bathroom door. Each time the door is opened and closed, the light toggle from ON to OFF and vice versa. No need for remote or anything.

It has the problem with the sensor because if no movement detected, the light will be off.

Anyway, why do you need the door switch sensor? If you have human presence sensor inside the bathroom already, the door sensor would be redundant. When I go out from the bathroom, the human presence is no more detected and the light is off. No need for door switch, right?

I've been looking at the sensor and so far all the PIR sensor is actually motion sensor. Need a thermal sensor to detect body heat even if no movement like Omron D6T thernmal sensor. However, this is module level sensor. You need to have some basic knowledge to integrate into system.

https://www.digikey.my/-/media/Images/Produ...1b-5bf745ee501b

Since you enter through the door, why not just flick the switch on your way in. Make it even simpler

After close door off but the motion sensor will not turn light on again if you shake your buttock?

Indoor or outdoor?

If you just google PIR motion sensor 240V, you sure can find many.

https://www.lelong.com.my/360-pir-sensor-ce...8-11-Sale-P.htm

Shipping from Penang... looks like

Or the simplest is just to use something like this:

https://www.11street.my/productdetail/110v-...CFUWhjgodgvkENw

I see. The one that built into LED light also review not good.

I think probably because the sensor got affected by heat from the lamp as they are close to each other, thus reduce sensitivity.

Lamp and Exhaust Fan not much of a current. You want to upgrade fuse? You mean the MCB? The light MCB is 6A, right? I would not recommend it to change to anything higher. The wire in the wall is smaller than the 3-pin socket wire.

Roughly the 6A can carry 240 x 6 = 1400Va already

After comparing PIR and microwave sensor, the microwave one is much better because it is not affected by ambient temperature like most cheap PIR sensor. Have a look at this:

https://www.lazada.com.my/products/360-degr...8&utm_campaign=[SSC-000000000000-00000-00000-0]:%20Smart%20Shopping%20Campaign&utm_term=[SSC-000000000000-00000-00000-0]:%20Smart%20Shopping%20Campaign_xxmo0000000at0000_c_pla-309746957645&adjust_tracker=t2v78t_5n20iw&adjust_campaign=1032211143&adjust_adgroup=54400014687_c_pla-309746957645&adjust_creative=309746957645_435695888_125142848&tracker_limit=1000000&ef_id=W5HLiwAAATfbGtNI:20180907005123:s

https://www.lazada.com.my/products/e27-micr...8&utm_campaign=[SSA-230000000000-00000-00000-0]:%20Top%20Furniture%20and%20Decor&utm_term=[SSA-230400000000-00000-00000-0]:%20Top%20Lighting_xxmo0000000at2304_c_pla-452269320600&adjust_tracker=t2v78t_5n20iw&adjust_campaign=1415046171&adjust_adgroup=55351307013_c_pla-452269320600&adjust_creative=452269320600_134836226_125131068&tracker_limit=1000000&ef_id=W5HLiwAAATfbGtNI:20180907005135:s

Yes. The microwave sensor will likely use either 2.4GHz or 5GHz same as WiFi router because it is unlicensed band. Unless you want to use your phone during shower ......

Have you tried to change the WiFi channel? I don't think the microwave motion sensor occupy the whole band. Probably your WiFi is occupying whole band?

The lighting MCB and the 3 pin socket MCB normally separated. The lighting MCB is normally 6A and the circuit supply 6 lighting points. The wire size is smaller than the 3 pin socket. The 3-pin socket uses 20A MCB and normally serves 2 sockets. These are standard practice.

If you add the two 13A sockets, it would become 26A but the MCB is only 20A. This is not a mistake. It is standards by TNB. If you power on both socket with same load, the max power each socket is only 10A

Water heater usually has separate MCB is originally wired by developer. It has 20A also and power the heater switch alone. If 3rd party install, they probably just tap the power from 3 pin socket.

Are you talking about the concealed junction box (black plastic) or on surface one. The concealed one can be located deep or shallow depending on how thick is the plastering. In my house some has longer screw than the others.

You do not want to cut wire too short because you can never elongate it in case you need it and short wires are even harder to work with. Long ... hard to tuck in everything in. I have at certain point put 3 wires because it is spurs socket.

One trick is to thin the insulator. The wires in the wall without conduit (or even with) are normally double insulated. You can remove 1 layer of insulator.

Smarthings supports many devices. Here are good resource on how Smarthings can be used on Xiaomi.

http://www.mysmartcave.net/category/home-automation/

https://www.chatteris.biz/blog/sonoff-basic...r-modification/

Nowadays everything has to be using smartphone. Otherwise, no smart