Help - new monitoring setup. Need advice on approach and emoncms dashboard

Hi Guys,

Any help would be appreciated as I am getting started and struggling a bit.
Have moved house to a large old property in Aussie Bush.

Its 3 phase with some old 3 phase gear and I am trying to get a handle on whats actually running and ultimately what costs what.

I have purchased an IotaWatt with 14 x SCT-013 CTs and purchased credits with and can log data ok. Really struggling with next step - what to log and then getting meaningful dashboard/reports/costs

What am I measuring?
3 Phase Input power to property (3 x CTs)
Solar Power Generation (1 x CT)
Hot Water (1 x CT)
Shed Power Board (3 phase, 3 x CT)
Garage Power Board (3 phase, 3 x CT)
Air Con (3 phase, 3 x CT)

Total of 14 inputs used and accounted for.

I assumed I could use Virtual Feeds to get Household usage (eg Sum of Inputs - Sum of (Shed+Garage+AC+Hotwater) = House).
This works on the IotaWatt but I can’t seem to see virtual feeds on


  1. What should I be monitoring/logging in feeds?
  2. How can I see virtual feeds so I can get house etc.

I want to be able to see power usage, generated, items and costs or at least percentages of totals.

I don’t think virtual feeds exist yet on, though they are certainly available in the Raspberry Pi version. (See Virtual feeds on

What you can do is add other feeds on the inputs page (and if necessary zero the value that’s being passed down so that the maths starts afresh).

A feed is where the data is stored - so whatever you want stored for display on a dashboard at some future time, bearing in mind that you can’t do sums on history.

That means, you must store “House” as a feed; you can’t do the sum House = (Inputs - Shed - garage etc) when you are viewing historical data.

Thanks for the reply.
I don’t seem to be able to manually add feeds on either.

Question on feeds:
Can I “hijack” my other feeds and do the sums on them and then log? For example I don’t really care to know each of the 3 phase lines for inputs and outputs and I can do some sort of summing on the inputs page when creating the feed.

If I sum them can I then save as a Feed, Power to kWh, and WH Accumulator or does that just log the basic.

Question on cloud/data logging:
I currently don’t have a device for logging. Its really easy for me to spin up an Amazon host if I can deploy emon to that - that I think is the best idea but I can also add a PI but then thats another local device to manage.
Am assuming that a standard linux install + some git should get it going?

How are you trying to do that?

Yes you can, but @pb66 recommends that you add feeds rather than inputs - the reason is down to having a set of data that is timed consistently. I guess as you’re paying for feeds, the technical advantage might be outweighed by the cost implication.

Yes you do, does that. Did you mean logging locally?

You can install emonCMS on any server (given the appropriate access and permissions). I’m not an expert - ages ago I installed it on a Windoze machine running WAMP, so I succeeded then. But some people who’ve gone down that route have had a few hoops to jump through. There are better people than I here to advise you on that.
By far the simplest is to download our SD card image and run it on a Raspberry Pi.

Hi Robert,

Thanks again for help.

Manually adding feeds:
I was trying to this by going to and then adding either inputs or feeds. I can see the 15 coming from my iotawatt but no option to add new inputs or feeds.

New feeds?
I had configured the iotawatt to give me some new outs - eg the Sum of my 3 phases for Inputs, Garage, Shed etc. but there doesnt seem to be a way to get that to

My thought was to use the inputs at and then define multiple feeds (assuming this approach is ok).
eg. what I was doing for the Grid Power which is 3 phase:

  1. Log to feed for each phase input
  2. Log Power to kWh for each phase input
  3. Log Wh Accumulator for each phase input

Then use Virtual feeds to create totals and work from there. This isn’t possible with

New approach - does this work?
What I am thinking of doing rather than above is repurpose the PhaseA input and use the +feed options to get

  1. Log to feed
  2. Log Power to kWh
  3. Log Wh Accumulator
  4. Daily total (Power to kW/d)
    (Assuming this gives me the totals)?

Can anyone comment?

I know that initially this is a lot of feeds and will cost a few $ for logging. I am not so worried about that as getting the data set and approach right. The actual electricity cost/savings will more than account for any feed costs.

You cannot add an input. That happens automatically as data comes in. You send the data from an input to a feed - you create the feed as you enter the details to “Log to feed” in the input processing.

Adding feeds:
Say you’re using Phase 1 input, and you have the 3 steps above.
Step 1 Log to feed
Step 2 Power to kWh
Step 3 Wh Accumulator

Step 4 will be Reset to Zero [back to where you started before Step 1]
Step 5 will be + Input 1
Step 6 will be + feed B
Step 7 will be + feed C

If your Iotawatt is sending the data, it should pop up on the Inputs page.

There are few people here who know the inner details of Iotawatt. If you have specific Iotawatt questions, I suggest The IoTaWatt forum is a better place to ask. That is managed by Bob Lemaire, its creator, and he and the other users there are more likely to have the specific knowledge to help you.

Hi Robert Thanks for the quick reply

To spell it out for this current noob… I really only need the totals logged so should be
For one of the Inputs eg Grid Power Phase A
(Do Summing)
Log to feed
Power to kWh
Wh Accumulator

Am missing the reset to zero etc logic?

The way the input processing works is the raw input starts at the top of the page.
With a few exceptions, the maths in each step takes the input coming down, does what it does to it, and the result drops out of the bottom to fall into the step below.

So if you don’t want to use the value that has been passed down, then you Reset to ZERO.
So for example, it’s nonsense to add a power to kWh - that’s when you must reset.

Does that answer your question?

Kind of. It looks like that would work for the total of a 3 phase feed.

How do I get a total for “Power to kWh” and “Wh Accumulator” for my 3 phases… ?

You have the total power for the 3 phases? Then you do the accumulation on the total.

Hang on - maybe I am now confusing things.

To go back a few steps:
I don’t have a 3 phase total and needed to sum them to get a 3 phase total.

I thought if I summed the 3 inputs (A+B+C) then logged feeds as follows I was ok
Log to feed
Power to kWh
Wh Accumulator

I got confused when you mentioned reset.

I prefer to do this at the IoTaWatt forum, but since it’s about the intersection of IoTaWatt and Emoncms, it might be helpful to leave some explanation here:

I’m assuming you are talking about defining outputs that you can see on you local status display and visualize in the locally served graph application. Those don’t get sent to Emoncms, but you can configure identical outputs to Emoncms (and/or influxDB).

If you configure basic emon service, IoTaWatt simply assumes you want to export all of the inputs. That works pretty well for single phase users, but three phase users typically want to aggregate the phases and track the total usage of devices. You can do that.

So the default looks like this:

Note the section labelled Emoncms inputs. These are IoTaWatt “outputs” (managed with the calculator) that will be sent in each frame at the interval that you specify. The numbers 1 to 15 are the “key” numbers that you will see in the Emoncms inputs display. Because of the protocol that is used to send bulk data to Emoncms, IoTaWatt must use the positional format to send the data and cannot send it using names.

So any of these can be deleted or changed, and you can add more to send up to 99 values to Emoncms. So to customize any of these inputs, simply click the edit button to the left of it and use the calculator to specify what you want

I put together this configuration as somewhat representative of what you described:

So now, by way of example, you might start changing those values being sent to Emoncms with the “calculator” editor:

So for the mains, we’ll send the total of the three as input key 2 to Emoncms.

The emoncms service now looks like this:

I’m going to delete the rest of the “preconfigured” nodes now before I build a new list.
Now I’ll add some of the other representative IoTaWatt outputs/Emoncms inputs
Now if you save this and start Emoncms posting, you will see 9 inputs active. You can delete the other old inputs greater than 9 to clean things up.
Once Emoncms receives tha first data packet, those inputs will have been crteated and you can use the Emoncms input screen to labelk them appropriately:

  1. voltage
  2. mains
  3. solar
  4. use
  5. hot_water
  6. shed
  7. garage
  8. AC
  9. misc (everything else)

You may choose to add others, but you have the idea. Now that these values are being posted to Emoncms, you can edit the inputs to create feeds by similar names, and to log power to KWh.

UPDATE: I made an error in number 9. I should have either not used parenthesis, or added the values inside the parenthesis:


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You are a legend.

Happy to talk about this in either forum - whatever works.

Will get another coffee and digest then apply this. Thanks so much. Really appreciate it.

The bit I was missing was tweaking the data in the Web Server. I had assumed outputs really were the outputs.
I ended up making both sets of outputs and keeping them the same so I could see status from the device and have something to compare to on

Some Samples of current state:

My plan is to give it a few days then start playing with and build a decent dashboard.

Please do let me know if there are any really good samples/examples I should look at for my situation.

That doesn’t look right. Some of the glaring red-flags are the 0.06pf on Mains2, the 0.67pf on Solar, and the imbalance of the AC phases.

This configuration looks eerily like the one I posted earlier as a representative config for explanation purposes. Phase assignment there isn’t necessarily what you have. There are a lot of incorrect combinations, and only one correct one. Do you feel lucky today?

This is strictly an IoTaWatt activity, and I see that you have another issue going at the IoTaWatt Forum, so we should work this over there, where other three phase users will be able to see how to work through configuring a derived reference install.

If you could post another status display and your input configuration display over there, I’ll get you started with determining the correct phase assignments. You’re going to need a decent resistive load, like a toaster, electric skillet, or electric space heater.

No worries - I will move this to a thread on the other forum and come back with your questions.