Energy meter pulse out

[Darren Beale]

Hello,

I need to hack together something to replicate the pulse output of an energy meter but my lack of electronics knowledge is hampering me somewhat.

I have a meter here which is generating a pulse and using an oscilloscope (on order) I hope to have the details (voltage, current, duration) soon though I've an inkling that it is around 50ms long and 30VDC/10mA (according to meter manufacturer instructions).

I've also been informed that I might need to use an "open-collector transistor with 100R series resistance".

I have an arduino, breadboards and some components. It doesn't feel like it should be a particularly difficult task which for someone with a modicum of knowledge and I see broken down into two parts 1) make the pulse 2) send it regularly, ideally with the ability to manually vary the frequency.

I could do with a starting point. Can anyone help please? Either on the characteristics of the pulse or how to generate it. I'd also be interested in something that I could grab off the shelf to do the pulse generation (my fallback option is to use a real meter and simulate consumption).

Thanks

Darren

[mikethebee]

Hello Darren,

There are many homecamper's with experience of such projects, I guess
they are all all a bit busy to pipe up here at the moment, so I'll ask
a couple of q's to get my head around your project.

My initial thought is that you could use the arduino as a simple timer
to create the pulses directly by turning an output line high and then
low with a variable time for each state. Depending on the current and
voltage needed at the other end you may need that transistor.

That raises a question: when you say 'replicate' do I take it you are
trying to simulate the function of the meter for input into some data-
logger/monitor?

You should generally consider 'isolation' between different circuits,
often an opto-coupling is used for total electrical isolation in
Utility applications.

Rgds, Mike.