Not sure where to put this, can't find any dedicated thread related to power meter.

I just got my UNI-T power meter from Taobao, going to use this to measure power consumption on my house appliances.

This power meter is running fine.
It measures its own power consumption too.



Good thing about this power meter is that, the battery is easily replaceable by users, using CR2032 battery.
This power meter able to work without any battery inserted.



When there is load connected, it shows power factor and power consumed at realtime, alongside with voltage and current.

The power consumed by the load, displayed on the power meter, is calculated with power factor considered, as such:
P = V * I * PF
Where P = Power, V = Voltage, I = Current, and PF = Power Factor

Here is the example when the power meter is connected to two units of GE T5 LED tubes.




From the power meter reading, V = 246, I = 0.077, PF = 0.83, hence P = 246 * 0.077 * 0.83 = 15.72 Watt, which is close to the value displayed in power meter, 15.8 Watt.

Digging out the specification of the GE T5 LED, the one highlighted in red is the model that I have:



One unit of the T5 LED rated as 8W, so two units of them will use up 16W, which is indeed inline with the power measured by the power meter.


Other functionalities of this power meter includes CO2 consumed, and cost calculation, you can set the cost per kWh in the power meter.
But one downside of the cost setting is that, it can takes up to only two decimal places, or XX.XX, but our TNB tariff for the first 200kWh is 0.218 per kWh, therefore the power meter can't input up to three decimal places.

Also, this power meter can't record the min and max of power, current and voltage, I would like to have such functionality as a plus.

Guess what, I stacked a power meter over another power meter.

This is Sonoff POW plugged onto UNI-T UT230B-UK, and then connect to my refrigerator.



The main reason I did this, is to see if the power consumption measure by two of this different power meter consistent or not.

It turns out to be quite consistent, therefore the power measured by Sonoff POW is also with power factor considered, hence both of the power meter are measuring the real power consumption.

If TNB domestic meter measure only real power, then the TNB meter should included PF into calculation right?

Apparent power = P * I
Real power = P * I * PF

Last time I saw a TNB meter in shop lot with LCD display, switching display showing kWh, PF, Voltage, etc...

They have store in 11street and Shopee, maybe can apply voucher.
http://www.11street.my/store/visiongadgetry
https://shopee.com.my/visiongadgetry

No offline as of now.

Working fine here, can see my fridge power consumption and control my ventilation fan using Sonoff.
I do noticed that Sonoff connection to server not so good, whenever there is download at full speed (around 10Mbps), then my Sonoff connection will broken.

Still online here, using Maxis Fibre.
Got one time all my Sonoff lost connection for very long time, I suspected something wrong on the Sonoff device itself.
I turn off and then turn on my Sonoff again, then connection to server success.

Flash custom firmware means will connect to different server?
If different server, how the smartphone app going to talk to the Sonoff?

There is a physical button on Sonoff, you can turn on/off power supply to the load only.

For me, I did use Xiaomi door windows sensor as alarm.
I automate the alarm arm and unarm using time.
You can set which door windows sensor will trigger alarm sound on the gateway.
When alarm trigger, gateway will sound and notification will send to your phone.
I also set notification to my phone only when the my front door is open, and leave opened for more than 1 minute.

Good thing about using Xiaomi as alarm system is, you don't have to hack wall to pull alarm wire, and have flexibility to add/remove alarm point.
Not so good thing is, the sensor is running on battery, and wireless.

Your office blocked i.imgur.com?

Can consider to get this Fujiaire aircond with WiFi add-ons.

http://www.11street.my/productdetail/fujia...10v9b5-42524065

Speaking of backup power project for whole house, what approach you are taking now?
I am thinking of using car battery + inverter, and also car battery charger when supply back online.

Thanks, looking good

If the feature you want such as electricity trip with notification, then the device must have backup power to do so, so as your wireless router and modem.
I thought you already have UPS that can send you email notification whenever house power trip?

Just came across this smart home brand called ROOME, when I was playing around with Mi Home app.

http://en.myroome.com/

This is the first smart stand fan that I came across.

SmartMi Fan
https://www.zhimi.com/fan/

It runs on DC motor, and has battery built in and remote control features.

I am wondering the nominal voltage published by ST of 230V, is this peak voltage?
http://www.st.gov.my/ms/web/general/details/144

The voltage measured by Sonoff or other energy meter also measure the peak voltage?