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"my last ade7878a project for raspberry pi (shield) was censored"

Just to make it clear to everyone reading this topic, Savenlid was asked to remove his design because it was potentially dangerous. OpenEnergyMonitor does not and will not promote designs that are unsafe.

That looks like an excellent IC.  I'd not even heard of using ultrasonic pulses to measure flow rates.  I'll be keen to hear how you get on.  For others wondering what it does, there's a good block diagram in their reference design here:  http://www.maximintegrated.com/en/design/reference-design-center/system-board/5969.html

i can inform that it does measure power very  accurately to +/-0.5% with respect to my "normal" meter from the power company

Subject to your choice of CT, and your calibration capabilities, it's not hard to get  0.1% accuracy out of those energy ICs.   In these parts revenue meters are only class 1, so in theory at least, you could use your energy monitor to calibrate your revenue meter!    But you really need a CT that has a very flat phase angle error (Vs primary current and Vs temperature).  It doesn't matter what the phase angle error is, but it really needs to be constant across the operating range.  And such CTs don't come cheap.

@dbc:

I used the CT-013-030 bought from ebay.

I loaded the internal 62 ohms resistor with 2x18 extra in series, making the total load 22.77 ohms

On top of that i have 2pcs  1K ohms on pcb that centers the output around GND.

I you want an ade7878a pi shield pcb assembled I can send you one.

I have all the software also,  i2c shared library, and ade itself as library and then some init code and some code that reads it.

I compile under virtualbox ubuntu and eclipse.

I will try to upload code later.

you can se curves at http://savenlid.se:5280/day.png

bottom curve black is revenue-meter scale to the right side for KW

bottom red green blue curves are phase a, b c

also shows accumulated energy for last 24hrs.

all data taken from sql database.

later today I think schematics for this maxim flow meter will be finsihed and I upload that also.

I send pcb to production later this week, friday maybe.

Trying hard to get hold of the audiowell DN20 tube.

I'm all set for power monitoring thanks anyway, but am keen to hear about your MAX35101 experiences.  Any idea what they charge for the MAXREFDES70# reference design?

$150, order online.

not too bad considering you get the tube included.

schematics attached.

dont know what refkit you refer to

this is the refket

http://www.maximintegrated.com/en/products/industries/metering-energy-me...

http://www.maximintegrated.com/en/products/industries/metering-energy-me...

the kit you talk about refdes70# is unkown to me I refer to the max35101 kit @ USD 150

3 pcb's ordered from oshpark.

so wait some weeks before assembled units.

also need to get hold of the spool body, but some programming can start without.

/Nicholas

See pointer above in my first reply.

I have an assembled pcb now

and also the brass tubes

"only" missing the pieze elements.

http://cosson.en.alibaba.com/product/579538475-211877940/abc.html?err_bi...

will post more once it progress further.

I have the hardware assembled now with brass tune, but still missing piezo elements.

project moves along slowly.

This seems interesting.

Anyone knows if there is such a thing as a prebuilt unit that has LED or S0 pulse output for kWh?

One that comes precalibrated?

Thanks

My "device"/pi-Shiled can to that.

it has leds for every single phase and can be setup for aggregated power on one output.

precalibrated it could be if i sold them that way. not sure if it would be wortwhile tough.