New system advice

Hello. I have had / will have a £2k water bill for a leak. I can now justify spending on a monitoring system!!!
I have a two wire water meter and reading the guide I need a emonth this will give me temp humidity and a input for the water meter ? (Going in calf pen so will be useful to have temp humidity)
I also want to add in the future two amp sensors to monitor power usage coming in and to the house feed (I can then calculate farm feed from difference)
So should my shopping list be

A raspberry pi 3 base
Power supply
Emon th
Do I need the 433 receiver on the pi base 3 ? (Little unclear to me)

Do do the water to start with

Emon tx at a later date for the power and outside temp sensor ?
Thanks for looking

Hi Andrew,

Yes you will need a RFM69Pi to receive the emonTH data.
You haven’t mentioned an SD card, that maybe as you are referring to a Raspberry Pi 3 with SDcard rather than without or that you are planning to build your own image.

I would also recommend a USB programmer if you do not already have one, they are relatively cheap and essential to update the firmware on a emonTH or emonTX.

However from what you say it might be worth you considering an emonPi rather the separate Pi 3, rfm69pi, emonSD and case. If all you want is 2 CT’s at a later date the additional equipment cost would be just 1AC/AC adapter and 2 CT’s, ~£30, saving the cost of the emonTx, of which you would only use 2 of the 4 CT channels. The emonPi has 2 CT channels and it is all housed in one box rather than separate emonTx and Pi/rfm69pi

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Two points - is there a reasonable path for the radio signal between the emonTH and the Pi - i.e. are there walls, how many and what material, and what is the distance? and you might (but shouldn’t) need a programmer to modify the sketch in the emonTH.

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Yes sorry was looking at the base which thought comes with a SD will check.
Am wondering about the ready made pi as being more plug and play.
How do I wire the 2 water pulse into it though. I have found some information for the th but cannot see what I have to do for the pi do I just put a rj45 on it ?
Also not sure I can put the box in a suitable position for the amp readers. To reach.

How long are the amp leads ?

I could put them in the first sub board for the time being but need to mindful that I will be taking another feed off at some point and as everything is armoured makes it not so straight forward for locating.
Sorry on phone at moment. Making it difficult to look things up

Two walls max. Two brick wide. About 40 ft
Programmer noted . Thanks

The CT leads are about 1 m, but can be extended using twin twisted screened “microphone” cable to about 10 m without any serious problem. If you have armoured cable, you’ll need to get inside the distribution board and put the CT on a single core - you might want to get your friendly sparks to do this.

Where is your water meter? My original impression is that it was near to the place where you wanted to put the emonTH. To connect it to your Pi, you will need to use the RJ45 socket (and be careful you get the right one, you might want to go via a breakout board).

I think the radio will be OK over that distance and two 9/11" walls (provided they’re not saturated with water!).

Thanks for the lead info .
Thinking breakout board and. Run longer probe leads . Is there a wiring diagram for pulse leads in a rj45 ?
Will put in spreadsheet and see which wins.
I haven’t fitted the meter yet but the easy place is above the calf pen didn’t mind the emon th there as small and easy to make ip65 and not 240
For the pi I am going to have to fit another garage consumer unit but would probably make a neater job and protect it more (have a spare it’s just weighing up the hassle of fitting it)
Thanks for the help

There is. It is in Resources > EmonPi hardware docs.

thanks, after a round trip of the internet I keep coming back to this option though as the total system cost is above a weeks wage i just need to make sure of a few more things before I take the plunge

as @pb66 suggested above the Emonpi is looking like a good fit ,

Hooking up the water meter via the pulse leads to the RJ45 (With a resistor to Gnd ) I would then use the instructions on the emonth page for setting up the graphing . fair enough

but will I be able to more than a Daily value I need to look by the minute? (Interested in how much the cattle are drinking each time they come to the troughs)
there are also number of other events during the day that I would like to see the water usage effect on.
(sounds like a simple request yet all the images and explanations I have come across are in days) I see that the Temperature Readings can be shown per min,
I would also then be able to add more pulse meters to separate emonth senders in time (Emonpi can only handle 1 directly connected pulse meter right ?) . thanks

You will see the pulse count increment each time the emonTH sends its data. And that can be changed by editing and reloading the sketch. The default is a little less than one minute, so probably OK for you.[quote=“Andrew_Griffiths, post:9, topic:2125”]
Emonpi can only handle 1 directly connected pulse meter right ?

That’s correct - as can an emonTH.

plunge taken, sure I will be back with questions but here is to hoping i have enough saved web pages