mellow.5
Posts: 1
Joined: Tue Jan 17, 2017 11:31 am

Power Meter 3AC 50Hz with 3 current and 3 voltage sensors

Tue Jan 17, 2017 11:53 am

Hi guys,

reading the energy meter every day does not fulfill my needs that's why I decided to try a RPi project.

I want to measure the current in all 3 phases of my house and the corresponding voltages to calculate the power and log it with the RPi. At the moment I don't care about visualization at all, this can wait.

I already read a lot about sensors and their connection to an ADC. From my point of view a MCP3208 or MCP3008 would be sufficient to do the job. My question is about sampling rates of RPi. Can I read 6 channels at about 500 - 1000Hz simultaneously because I want to log the sinus shaped currents and voltages. Another way of data reduction with my capabilities would be calculation of the power of each phase in analog technology and than provide the let's say average power within 1s to the ADC.
But I'd really prefer the digital logging of sinus waves.

Thanks for your help.

User avatar
brekee12
Posts: 335
Joined: Wed Feb 03, 2016 3:36 pm
Location: HU

Re: Power Meter 3AC 50Hz with 3 current and 3 voltage sensor

Tue Jan 17, 2017 12:48 pm

To measure three phase it is very complicated. Not only question of ADC but isolation is crucial point of your project. The best way to study electronic power meter IC-s.
Brekee12
on a Raspberry B+ with whezzy, two Zero with Jessie Light

NicoVanDerDussen
Posts: 74
Joined: Sat Aug 24, 2013 2:41 pm

Re: Power Meter 3AC 50Hz with 3 current and 3 voltage sensor

Tue Jan 17, 2017 12:57 pm

Why not use a commercially available meter of the shelf?

I'm planning to use one emitting ticks at 0.01 kWh usage.

Already using a water meter with a reed switch closing every 0.5 liter.

Works like a charm
Setting up your Raspberry Pi to work with a 3G dongle http://nvdd.info/11gKrsZ

Moe
Posts: 230
Joined: Sun Jan 25, 2015 2:44 pm

Re: Power Meter 3AC 50Hz with 3 current and 3 voltage sensor

Tue Jan 17, 2017 10:54 pm

The Pi and the MCP3208 should cope, you just need add up the bit rates and check that the SPI bus is fast enough. Though it seems to me that you could get good measurements at much lower sample rates.
Submarine communication systems engineer and amateur robot enthusiast.

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