Solar and Generation metering with DIN rail meters - weird values

So folks I have a Flukso meter connected to two DIN-rail meters with pulse output in the meter box. One meter monitors consumption and the other monitors the power coming from the solar inverter.

Data is coming out fine, except that my consumption is closely following my solar generation.

See here: http://pvoutput.org/intraday.jsp?id=13740&sid=12392

It seems that generation is getting seen as consumption. When generation exceeds consumption, the consumption meter reads "reverse current" on its external panel but I'm assuming it's still generating pulses.

Right now, the solar output feeds into the output side of the consumption meter. Should I feed the solar output to the input side of the consumption meter? Or is there a programmatic change I can make to have the data calculated correctly?

I'm sure the answer is simple...but I'm very confused at the moment.

Kaldek's picture

Actually....this is weird. It appears that it was working up until 9:30 this morning when the consumption value dropped to zero. It then suddenly shot up and started tracking with the generation value, minus a couple hundred watts.

My consumption meter is 1600imp kw/h with a correction of 0.625 applied to it.

It's almost like the Flukso is now monitoring ports 4 (consumption) and port 5 (generation) as the same...

gebhardm's picture

See https://www.flukso.net/content/r223-release-notes --> "Known issues:
Real-time readings are not correct for pulse inputs with meter constants that are not an integer fraction, see this forum post. So constants like 0.5, 0.25, 0.2, 0.1 will work correctly with the real-time interface, while 0.625 and 0.4 will cause bogus values." - https://www.flukso.net/content/peaks-and-troughs-minute-dash
Also check on how you defined the second source within pvoutput - do you use a summation?

Kaldek's picture

OK I've confirmed that the main meter still registers pulses when it's in reverse current.

If someone has any advice that can assist with giving me a mental shortcut I'd like to hear it. I basically want to separate consumption from generation.

Right now my brain is telling me to wire in the output from the solar meter into the input on the main consumption meter. Someone tell me if I'm wrong?

Kaldek's picture

Thanks Gebhardm but that's not what I'm seeing. The data in pvoutput matches what I'm seeing in Flukso so it's not an issue with pvoutput.

Here's the graph from Flukso:

https://lh5.googleusercontent.com/-cYXCuFdy55Q/Uhr5PdJ07SI/AAAAAAAADw8/C...

This graph seems to be telling me that I need to re-wire the solar output into the input of the consumption meter. Am I right?

gebhardm's picture

The diagram seems OK - this is the standard wiring here in Germany for separate generation and consumption metering.
If your main meter displays "reverse current", this indicates that it is a bi-directional counter without backflow barrier, right? An old Ferraris counter then would run "backwards" in the case of "reverse current" as more power is supplied on the consumption side than consumed.
So, you currently connected the PV on the consumption side, correct? In this case additional to the pulses for energy flow there should be a connector indicating the "reverse direction" of pulses - but this the FLM cannot detect...

Kaldek's picture

Thanks Gebhardm, seems we're all in agreement what I stuffed up.

My electrician is going to fix it this week. Once it's all done I'll make some videos on the right wiring layout and put them on YouTube. Always best to pay it forward!

bazzle's picture

Is there also one mains meter (electricity supplier) programmed to read bidirectional for solar in the supply from the street wire?

gebhardm's picture

At least in Germany consumption of the inverter at night is neglected, so no bidi counter required, just supply towards the mains.

Kaldek's picture

Bazzle, the power company meter can read bidirectional, and we even get paid for every kilowatt/hour we export to the grid. I get paid 31 cents per kw/h until December 31st, 2016. Then 8 cents per kw/h after that. The system will be paid off by then (it's a 5kw system).

Right now the power company owes me $1,300.

bazzle's picture

Good.
So is mine in Oz. I'm on 66c until ?? and $1800 in front atm :)

Kaldek's picture

Ok, re-wiring job has fixed everything up and I'm now getting clean data.

bazzle's picture

Can you post the updated circuit?

ta