OpenEnergyMonitor Community

Economy seven metering

Tags: #<Tag:0x00007fc9b66248c8>

Looking at getting an eon setup, but I have an economy seven meter - which has two pulse outputs.
The Economy 7 meter has a bit of a wonky clock (not nearly enough that that the energy company cares), so the different pulse outputs are the things that tell me when I am on cheap rate power.

Looks like the emonpi only supports one pulse sensor - is that a hardware limitation on the Arduino side, or on the Pi side?

Whilst I am fairly happy to pay for the overall system (case and all) to help cover dev costs paying another 80 quid for a second pulse sensor seems a little OTT - so is there another way?
I presume an arduino nano every would have sufficient counting capacity, it’s just getting that data back to the Pi that’s the question…

As far as I am aware there is never a case when the two pulses would be active at the same time - so I might be able to combine them and have something else spot which one is firing to see which power rate I am getting?



It’s a limitation of the Atmel '328P processor, it has two interrupt inputs, and one is committed to the radio.

However, it is possible to have a pulse input (or two) on a Raspberry Pi, the details are here:
Directly connecting to Optical Pulse Counter with RPi? but it doesn’t appear to be physically possible to add those connections to an emonPi without modifying the case.

So I think the question becomes: do you need the analogue current and voltage inputs of the emonPi as well as the pulse inputs? You will if you have your own generation, because pulse outputs tend not to work (or worse, work wrongly) when exporting. But as you don’t mention that, you might get all the information you need from the pulses.

Yes, eMon… Stupid drunken elf…

Adding them to the pi directly is well within my current capability… The desire for the current clamps was to measure the EV charger directly as much as anything else.

I might start off with just the two pulse sensors then, since I have a Pi on my desk already.
Once I have this done here I’ll package up a much bigger system for my parents house, they have PV generation, and a power wall…

Thanks for the link.

Thanks Robert…

Two pulse counters… and I now have evidence that my meter is borked.
This is going to be fun conversation with my supplier.