Setting up a CT sensor with an emonBase

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I’m setting up an emonbase and I’m very new to the open energy monitor. I’m wanting to use the emonbase to measure power usage of an electrical appliance and I’m currently setting it up. I have a CT sensor plugged into the emonbase ready to go but I’m unsure how to add the correct inputs as it currently doesn’t have any. I’ve looked through the formats for a few but any I add don’t work as they don’t update. Can anyone send me in the right direction. Thank you!

Welcome, CTGuy, to the OEM forum.

I’m puzzled. You say you have an emonBase, with c.t. plugged in? The emonBase does not have any analogue inputs for a c.t. - are you sure you don’t have an emonPi (in the aluminium case with a 2-line LCD display) instead?

What exactly do you mean by that? Where are you looking, and what are the “formats”?

Hopefully a very silly question - have you looked at The Guide - and if you were following it, how far have you got?

No I mean emonBase. It has a media jack to plug it into. Can it not be directly plugged in this way to take measurements or will an arduino have to be connected? And I meant to say how do I make an input for measuring power usage for an emonBase. So EmonCMS HTTP input API is what I mean.

No, it cannot - to the best of my knowledge anyway. And then, even if you could use it as a “microphone”, you’d need the software to process the signal - and again to the best of my knowledge, that doesn’t exist either.

I think there are three ways you can go:

  1. Add an emonPi PCB from here. This would give you two current and one voltage, temperature and pulse inputs, and the Atmel 328P processor that does all the energy calculations. It connects serially via the GPIO port.
  2. Add an emonTx, which would give you 4 current, one voltage, temperature and pulse inputs, and normally connects by radio, but it can be connected serially too.
  3. Add an Arduino Uno and an emonTx Shield - effectively the same as an emonTx.

When you add one of those, and set up emonhub.conf appropriately (if you don’t have one of the default set-ups), then the inputs will pop up in emonCMS automatically.

Awesome, as I say I’m very new to this :sweat_smile: You are right apparently the media jack can only be used as an output for the emonBase. Is it possible to use an arduino and plug it into the emonBase via usb to record data? This is what I’m thinking now you see. Do you think it’s possible this way?

Sorry, I’m not going to watch 6 mins of youtube.

Some Arduino versions can accept the emonTx Shield and do USB as well, and some cannot. I’m not up to date on which can and which can’t. You can add an ESP8266 to an emonTx - even though you’ve already got the 433 MHz radio link, but all that’s rather pointless as you’re obviously planning to have the RPi close to the measuring point and you can easily do a direct serial connection via the GPIO, which will be much more reliable and cheap.

The emonbase does not do any measurement of energy use. It is simply designed to receive data (either by a network connection or by Radio Frequency (RFM - hence the extra board) and log it.

If you want to measure energy use it is likely you need to buy some additional equipment to measure the energy like an EmonTX.

Brian, I think that’s pretty much as I wrote in posts nos 2 & 4 above.