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Pulse count not correctly set up, need advice

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I have some problems understanding how to set up my pulse counter. The energy meter is saying 2000imp/kWh. The pulse counter shows a green blink for every red blink from the meter, it does not seem to miss out an any. And it is always blinking (main household meter). From reading the guides here I would say that this is how the input config should be to convert to pulsecount n to energy in kWh:

energy[kWh]=n_meas[imp]/2000[imp/kWh]=n_imp*0.0005 [kWh]

This is how it is implemented in emoncms:

But the resulting energy per day number is way too low by about - but not exactly - two decades when compared with CT readings (which usually is about 1-2% from the energy company numbers). I do not have too much stats to show yet due to other problems.

Is there something I have missed completely?

Hi, my setup is a bit different in step 1. I don’t calculate the pulse delta between reads.

Have you seen the Optical Pulse Sensor setup guide https://guide.openenergymonitor.org/setup/optical-pulse-sensor/?

I tried something similar, and it does not work in my case:

Since the meter is defined as 2000 imp/kWh I multiply the pulses by 0.5 to get Wh. Then I used the kWh accumulator, which I guess will give realtime accumulated Wh (not kWh as I have put into the feed name). The funny thing is that this value becomes a constant with the value 3.00.

Finally, my thought was to multiply the Wh increments with 1000 to get kWh before running the “Wh incremements to kWh/d”. This was obviously wrong, it should have been multiplied by 0.001. Anyway, both the scale and kWh/d number value are wrong (not just the 10^6 factor error). So I’m at loss how to configure this.

I did try and read the setup guide, but so far I do not get any sensical outputs…

I just now tried to change the first multiplier from 0.5 to 0.0005 to actually get Wh. For some reason, the number 3.00000 now started to get increments. I’ll wait a couple of days to see what this results in.

Update: This is the input config now:

The kWh accumulator seems to work perfectly. Here is a 900s average plot with CT measurements (blue line) and pulse counts overlay (yellow circles). They match more or less 100%.

The Wh increments to kWh/d is not working as expected, though:

Typical daily values would be 30 to 60kWh/d, while the delta values here are < 1kWh/d. I experience this on the daily increments feed from the CT’s as well, where values are == 0. They are configured like this: