You make a valid point; my solution may not work in your specific situation, like in the bedroom.

However, it works well for me in the kitchen. As soon as someone enters the kitchen area, the light automatically turns on, followed by the fan. When the person finishes cooking, washing, or other tasks, and leaves, my home automation system turns off both the light and the fan.

The mmWave presence sensor is highly effective at detecting micro-movements instantly, while the PIR sensor works well for identifying moving objects that generate heat.

By combining these two sensors, the mmWave sensor turns on the light when it detects micro-movements, while the PIR sensor observes the area and activates the fan. It then remains on standby until it no longer detects the heat-emitting object or when it becomes stationary, at which point it turns off both the light and fan.

This cycle continues to repeat.

Thus, we need both sensors and not one of them for places with moving/spining fan.

I think your problem is not with the smart switch but with the AC (Alternative Current) noise from your inductive load.

You either change the LED light to one with better handling of EMI or install EMI filter.

Like this, which is more effective but may post a challenge to you.

Other option will be Ferrite core like this one .

It will suppress any AC noise to certain degree.

If you're noticing that the LED light flickers when it's turned off and your wall smart switch uses a solid-state relay instead of a mechanical one, I suspect that the solid-state relay's optocoupler is sensitive to the incoming AC noise. To reduce this noise, you could try replacing the electrolytic capacitor on the secondary side with a solid-state capacitor , which offers better ESR (Equivalent Series Resistance) and improved noise suppression.

Based on the image you shared showing a burned-out or broken PCB track, this damage is likely due to a high voltage surge, such as one caused by a lightning strike.

To prevent this from recurring, replace the damaged wall switch with a new one from a reliable brand of your choice. Additionally, add a MOV/Varistor (10K431K) between the incoming Live and Neutral wires. This applies if you're using a smart switch with a neutral wire setup. If you're using a bypass capacitor, however, the MOV may not function as effectively.



The MOV (Metal Oxide Varistor) will help protect your sensitive electronic devices by absorbing excessive voltage before it reaches them.

Be sure to select a 10D431K specifically, as other values may not provide the same level of protection.

NOTE: Those staying in condo or high-rise building may not require such a protection as the building management already installed some kind of protection to prevent the voltage surge to its tenants.

An RCCB is not designed to suppress high incoming voltage spikes; rather, it detects any imbalance in the current passing through it—such as when some of the supplied current leaks to the earth wire via an appliance—before cutting off the power supply to protect the appliance.

For comprehensive protection of the entire house, a Surge Protection Device (SPD) is more effective. The ABB OVR T2 protection begins at 275Vrms, similar to the 10K431K MOV.

I checked my old mechanical doorbell and it can only can supply up to 12Vdc. Based on the Reolink doorbell requirement, it need 24Vdc and 12W. Thus, you cannot depend on the supplied voltage coming from this mechanical doorbell.



If I were you, I will remove the content of this doorbell and replace it with all-in-one power supply module.

I will pick HLK-20M24 which can supply 24Vdc and up to 20W.

You need a handyman for the job with soldering iron, some wires, wire connectors, insolation tape, double-sided tape and digital/analogue voltmeter.

I suggest to you to forget about recycling the old Chime box's power supply for your new Reolink Doorbell. There are too many unknowns such as output voltage, power rating, when the capacitor's electrolyte going to dry up and their ESR (Internal resistant of the capacitor, if any).

I have upgraded version for you. Buy a large enough wall mount WIFI enclosure that can house a power extension, chime, doorbell's power adopter etc. Do share with us the look before and after the upgrade.

To wire up the Voltage Regulator (20M24) to your existing chime doorbell wiring, it needs a soldering iron, some loose wires and wire connector.

Do ask your electrician whether he have the soldering iron and loose wires for the jobs.

This is typically how I ensure the connection between the Power Supply module's pin (A) and the wire (B). First, apply soldering lead to both the pin (A) and the wire (B) separately. Then, solder the pin (A) and wire (B) together to form connection C.

If the total height of the module and soldered wire ( C ) exceeds the space in the doorbell chime box, bend pin (A) before making the connection.

Once both pins are soldered (for both the input and output voltage pins), your electrician can use 3M double-sided tape to secure it inside the emptied doorbell chime box and connect the wires to your existing doorbell wiring, via wire connector D.

No need to worry too much—let the electrician handles the process of emptying the chime box and installing the module inside for you.



In case anyone want to DIY this project but limited by basic tools, you can buy this Power Supply Module. Note, due to its size, it may not fit into your existing chimebox. So, buy a suitable size of wall mount Wifi enclosure box or something similar to cover it up. If possible, get an electrician help to install for you.

Any loose wires will do, and I believe your electrician will have some spare/loose wires, just need to inform him first.

If you want to monitor the electricity generated by each micro-inverter or even by the individual MPPTs of each micro-inverter, you can install the Hoymiles Wi-Fi integration in your Home Assistant app.

By combining data from the Hoymiles Micro-Inverter and the Bidirectional Energy Monitor, you can populate the Energy Card (Home Assistant Energy Dashboard) for a clearer view of your energy distribution.

For high-power appliances like water heaters or air conditioners, I prefer using heavy-duty relays rather than standard or miniature ones. Regular relays aren't suitable for high current loads. For example, if you run your washing machine on hot water mode, you'll notice that the 3-pin plug gets hot and in the worst case, it can even melt the plug and socket.

Consider using a 30A relay module that supports Tuya (Wi-Fi/Zigbee) and 433MHz. It can pair with up to 8x 433MHz wall switches (1-gang).

You can install the relay module inside the water heater casing, hardwiring the existing switch wiring. Then, replace the original water heater wall switch with a 433MHz wall switch, placing one at each bathroom entrance for convenience.

If you want to use Tuya with WiFi and avoid intermittent connection drops, make sure your current WiFi router supports static IP assignments for each device. If you plan to upgrade your router, consider a GL.iNet router, which comes preloaded with OpenWRT and receives long-term firmware, security, and feature (AdGuardHome/TailScale etc) updates.

Also, avoid using the native Tuya add-on in Home Assistant. Instead, use "Tuya Local" (not "Local Tuya").

With Tuya Local and a static IP for each Tuya device, you'll no longer rely on Tuya’s cloud service, which can disconnect frequently and often requires a "trick" to restore the native integration when the connection is lost.

As for smart wall switches, buy just one unit first to test it out. Replace your existing switch and check if it physically fits in your wall switch box, as this wall smart switches can sometimes be too bulky to fit. If it doesn't fit, you may need to explore alternative options.

It should be totally fine to replace your current switch with a 2-gang smart wall switch. Just make sure to get one that doesn’t need a neutral wire (No Neutral), since your setup doesn’t have one.

Once you’ve got the smart switch up and running, you might also want to upgrade your fan regulator to a Universal Ceiling Fan Remote Controller, makes things a lot more convenient!

DC ceiling fans are getting cheaper these days — definitely worth upgrading. Same goes for those universal ceiling fan remote controllers, now selling for under RM20. Not bad for occasional use or if you’re still using modern/classical looks AC fan.

@lucaswjk, after you’ve upgraded to DC fans, have you considered integrating it into your Home Assistant setup?

If you want to control your fan (on/off, speed, lights) from Home Assistant, you can try using the Sonoff RF Bridge R2.

With a bit of tweaking, you can flash it with ESPHome and make it work with most RF remotes.

It’s super handy, lets you control stuff like HA managed fans or lights from RF remote, without needing to open the HA app every time .

Smart switches typically have a bulky back section, often around 1 inch deep, which makes it difficult to fit them into standard wall housings. It's best to purchase a sample unit of the smart switch and give it to the construction worker in advance, so they can create a deep enough mounting box to accommodate both the switch and the wiring. Additionally, make sure to request that a neutral wire is pulled to the switch location as well.

Regarding your second request about turning on the downlight before arriving home, while there might be simpler methods, I personally use Home Assistant (HA) and Node-RED to handle this task.

When I’m about 50 meters from home, I check my HA dashboard’s CCTV feed to see if the gate is already open or in use. If it’s not, I press the autogate button on the dashboard. This action opens the gate and, if it’s nighttime, also turns on the car porch light and fan. Additionally, it switches on one of the hall lights to alert anyone inside that the gate has been opened, a useful reminder, especially since I’ve had instances where someone exited the car porch and forgot to close the gate.

Are you using the Broadlink app as a standalone smart control app, or have you integrated it into a centralized smart home platform?

There’s no problem using a switch with a higher amp rating for a water heater or air conditioner. The only drawback is that it might be a bit more expensive or unnecessary (“overkill”).

On the other hand, using a switch with a lower amp rating can be risky because it may cause the switch to overheat or wear out faster.

Remember, a switch’s job is only to turn the power ON or OFF. The real protection comes from your distribution box:
- Circuit Breaker (CB) protects against overcurrent/overload.
- RCCB protects against current leakage (to prevent electric shocks).


Before buying a 40A (or 20A) smart switch, make sure its physical size can fit into your existing switch box. Keep in mind that the Live and Neutral wires inside your current switch box may already be taking up about half of the available space. You can stack up spacer (smart switch wall spacer socket) to increase the volume size of your existing switch box. Technically 20Amp switch is sufficient for 2.5HP AC for both Conventional or Inverter type.

Since you’re already engaging an electrician to install electrical wiring, you might want to consider adding the following:
- SPD (Surge Protection Device) in the DB box to protect your smart gadgets from lightning strikes and electrical surges.
- Smart RCCB (to replace your existing RCCB) with auto-reclosing function, real-time power usage display, and current leakage monitoring.

I recently installed one in the upstairs DB box after my old RCCB kept tripping occasionally. Using the real-time readings on the unit (and on my smartphone), I was able to identify two leaking devices:
- An old laptop power adapter leaking about 10mA.
- A water heater leaking 20–30mA.

To prevent further issues, I’ve turned off the circuit breaker for the water heater.

The auto-reclosing feature is especially useful, it automatically turns the Smart RCCB back on if it trips unexpectedly (e.g., due to lightning). However, if the RCCB keeps tripping after several attempts, it will stay off until someone manually resets it or checks the wiring for faults.

If you’re planning to install a solar system in the future and want to monitor both import and export power, consider getting a bidirectional RCCB.

Here the link for Three phases

Here the link for Single Phases


For the SPD, there are many to choose from online store.

The burn mark is not due to product quality issues but external factor such as lightning strike in your area. Installing SPD will protect your electronic gadgets. The purpose of SPD is to trim the incoming excessive voltage spike not more than ~275Vac.