3 phase energy meter

Hello there

i am searching for guide how to build 3 phase power energy meter in my home.

What devices i need for this and what is the best way how to do it?

thanks in advance

neznamnista:
Hello there

i am searching for guide how to build 3 phase power energy meter in my home.

What devices i need for this and what is the best way how to do it?

thanks in advance

An "energy meter" would be a kilowatt hour meter, so you will need a real-time clock and three current transformers and associated circuitry. You can search the Arduino for those terms to find more information.

Paul

There are numerous ways of approaching a project like this, the suitability of which depends on existing skill base, resources, and suitability to be interfacing with mains electricity and installations, and desired outcome.

The question indicates you are at the beginning of the research phase, therefore some reccommended google search terms could be, open source energy monitors, open source interfacing with commercial energy meters, devices for three phase energy monitoring, application notes for three phase energy meter reference design.

Any or all of those type of searches will provide plenty of initial information to investigate which should be really helpful.

Aliexpress
Buy a 3 phase meter with rs485 output.
It's the safe way.

In the States very few homes have 3 phase

Since you are measuring a home, rather than 3ph gear, you might be better off with three single phase kWh meters. Plenty of them about, and they typically have isolated 1Wh output.

i would like to have online monitoring of power consumption

what devices you suggest?

neznamnista:
i would like to have online monitoring of power consumption

what devices you suggest?

Aliexpress
Buy a 3 phase meter with rs485 output.
It’s the safe way.

rs485 module
esp8266

@dave-in-nj i found only one seller with this 3 phase meter with rs485 for almost 100 USD

is it possible to build it for less money?

Openenergy.org

You can do each phase as separate individual phases
CT or current transformer
Regular transformer for voltage

neznamnista:
@dave-in-nj i found only one seller with this 3 phase meter with rs485 for almost 100 USD

is it possible to build it for less money?

What is your time worth to you?

Paul

"is it possible to build it for less money?"

Unless your system is way out of balance, you should be able to just one of the phases just as in a single phase system to get the info you want. Use the forum search box in the upper right and search for key words like "power monitor" and similar.

Have you looked at https://openenergymonitor.org/?

i like @dave-in-nj's idea....i found this on aliexpress

but how this to connect (wiring diagram with esp8266 with Arudino IDE, but without arduino uno) to be monitored online (pc, phone)....

There was a device put out by clipsal Australia called cent-a-meter.

Wireless transmission from tx to rx at around 30 metres.

Was available as a 3 phase unit but not that common.

Easy install, a “split” ct clipped over the main incomer active and a couple of AA batteries.

Amazing really as most Australian installations are an all metal meter box where the tx was fitted and yet seemed to get good range. Most would sit the receiver/readout on top of the frig inside the house.

Haven’t seen them lately but surely Clipsal were not the only ones to have come up with this idea.

PDF below.

It was a novelty thing at the time offered by the Aus Gov. where one would pay $50 and a lecky would come out and fit the unit along with 3 or 4 “efficiency” fluro light bulbs.
Worked fine but people being what they are, and government people not having the foresight, the batteries were never replaced in the tx unit.
AND why would they when in most instances it was in behind the main metering panel so for one, they probably didn’t know it was there, and two, for those that did, most weren’t prepared to go digging around behind a panel with single insulated cabling and good possibility of getting an electric shock.
Gov never gave them any spare batteries anyhow…:slight_smile: :slight_smile:

https://www.energymatters.com.au/clipsal-centameter-energy-monitoring-device-p-924.html

Cent_a_meter.pdf (425 KB)

bluejets:
There was a device put out by clipsal Australia called cent-a-meter.

Thanks for bringing this up, I don't know if that device is still around, but there may be something like it. I got the impression it was more commercial/industrial but it might have been killed off by the plug-in ones. About the only information I remember on it was actually an Arduino project by Freetronics, using their wireless shield, I'm not sure they did much about it, and I don't recall any ads for the meter. It used up to three single-phase clamp-ons. I was mentioning that approach above, but it didn't spark any interest.

neznamnista:
i like @dave-in-nj's idea....i found this on aliexpress

Nuevo Sensor transformador de corriente de núcleo dividido YHDC 30A SCT013 0 30A AC no invasivo|transformer current|transformer transformertransformer ac - AliExpress

but how this to connect (wiring diagram with esp8266 with Arudino IDE, but without arduino uno) to be monitored online (pc, phone)....

If you investigate more deeply the open energy monitor links you're been provided several times by various contributors, the documentation is there (code and schematics) to build a simple prototype using a clip-on CT like that, and decide if that is the type of solution you wish to develop further.

You do not necessarily have to follow the entire archtecture of that project, if good data is pulled into a wifi-capable device such as an ESP32/8266, the data can be sent off to a cloud service of your own choice such as Thingspeak, or displayed/evaluated locally by various methods.

IMHO, 100Uusd for a 3-phse meter with rs485 is a darn good price for what you're getting, and solves many issues for you, unless it's "in-line". Non-contact (apart from a plug and socket for the voltage refernce) via Clip-on CT's is the best option for home-installers, unless you or somone you know is a registered electrician and can safely install an in-line meter......

for 3-phase you should get an UNO and the energy mon shield.
And three CTs.
Get one transformer
This is NOT ideal
But will give you one channel of actual power and two channels of APPARENT powers
Get one Esp8266 and connect to the UNO. there are many tutorials how to do that.

If you want actual power readings then you will need to make your own circuits. One for each phase.
The UNO has tthe ADC Inputs you need
The ESP8266 has the WiFi you want.

Cost comes down to how accurate you want to be and how good you are in Making your own circuits.

the ESP8266 has only one analgo input.
if you only want one CT like in your link,
you will need to use some resistors and a cap to make it work.
google openenergymon.org arduino to see the schematic of what you need
with one ESP8266 and one Analog input, you can see one channel of the 3-phase and then only current
ESP32 has more analog inputs and the best thing is that the sweet spot of the ADC is in the center, where you would use it most.
An Arduino UNO and a ESP8266-01 might be cheaper

i just want to use esp8266 with esp-01 for sending data to adafruit or to be readable

yes i can use also CT because here we have 3 phases

does any know how to do this

neznamnista:
i just want to use esp8266 with esp-01 for sending data to adafruit or to be readable

yes i can use also CT because here we have 3 phases

does any know how to do this

You do not have to have 3 phases to use a ct.
However, it might be a good time for a bit of advice regarding ct's and their use.
Never allow an open circuit secondary on a ct when power is applied to the primary, in fact a good idea to keep the shorting links in place until all is powered down and ct's connected to their circuitry.
An open circuit ct will produce lethal voltages so be warned.

neznamnista:
i just want to use esp8266 with esp-01 for sending data to adafruit or to be readable

yes i can use also CT because here we have 3 phases

does any know how to do this

We have told you multiple times on this thread
google: openenergymon.org arduino
since you are just a beginner, forget about trying to read 3-phase, it is not a beginner level thing.
also, since you are a beginner, forget about getting actual current readings, get apparent readings.
for the beginner, they are close enough and will follow power used.

The WEMOS D1-mini or any development boards will act just like an UNO in that you connect power and can program it with the Arduino IDE.
since the ESP8266 has only one input (0 to 3.3 volts on the development boards) you can only measure one thing.
order that CT you had linked to and make your own circuit as shown on openenergymon,org