Energy monitoring equipment / systems?

[LRSFC_DanJ]

As part of the action we're taking on the climate crisis and working towards getting our organisation to net zero, we want to start a pilot programme of monitoring energy usage in certain areas of the college.

 

Initially we were thinking of using equipment similar to the emonTx/emonPi (e.g. see here: https://shop.openenergymonitor.com/energy-monitoring/) with clip-on CT sensors that can clip on to the distribution board cables in the area we want to monitor.

 

However we want to make sure we look around at other alternatives as well and I was wondering what equipment other organisations use for this?

 

Key points are:

• We need something that can feed the data into a central database so it can be queried and reported on - so something that's just a portable meter with an LCD display is no good.
  
• As it's just a pilot programme, we don't want anything that's invasive and requires actually wiring in to the electrical circuit by an electrician - hence the clip-on CT sensors
  

When searching I did come across IoTaWatt as well but this seems to be an America-only system, does anyone know of any others?

 

Thanks,

 

Dan Jackson (Network & Systems Engineer)

 

Long Road Sixth Form College

 

Cambridge, UK.

Edited September 8, 2022 by LRSFC_DanJ

[mavhc]

I use Estron SDM series with RS485 Modbus connectors, about £15 from china. They have CT versions, you'd have to wire in 240V directly though, but for CT versions don't need to take apart a fuse box. When you want to install them full time you can get ones that you just wire in series with the circuit.

 

It's not a complete solution though, you'd want to read the ModBus data and send it to mqtt and store in a database.

 

I'll probably write up my setup when I get time and post the code

[LRSFC_DanJ]

I use Estron SDM series with RS485 Modbus connectors, about £15 from china. They have CT versions, you'd have to wire in 240V directly though, but for CT versions don't need to take apart a fuse box. When you want to install them full time you can get ones that you just wire in series with the circuit.

 

It's not a complete solution though, you'd want to read the ModBus data and send it to mqtt and store in a database.

 

I'll probably write up my setup when I get time and post the code

I can see from their website https://www.eastroneurope.com/products/view/sdm630mct-lorawan-mid that they have some LoRaWAN ones similar to the emon stuff, but it doesn't seem like they do base stations / gateways to go with them. Is there a standard for these sort of things?

[dmj]

• As it's just a pilot programme, we don't want anything that's invasive and requires actually wiring in to the electrical circuit by an electrician - hence the clip-on CT sensors
  

 

Consider that the clip on sensors measure the electrical field induced by the wire, so if you have a positive and negative together in a single cable they will cancel each other out. Your fuse boxes may already have individual positive/negative cables exposed but you need to check, and you might be required to get an electrician to install it in any case.

[ZeroHour]

Sorry I replied on twitter first, I think that the emonTx approach may be the best given what you want to do. I did suggest the Shelly EM and you can do some extra monitoring with multiple EM's or the other Shelly plugs but it will be cheaper with the Emon I suspect.

There is https://www.amazon.co.uk/gp/product/B08CJGPHL9/ref=ox_sc_saved_title_2?smid=A39JNSYFEEWBC5&th=1 but its more consumer and its going to be harder to get the data out. I just liked the Shelly approach if your not planning on covering each ring.

[dmj]

This thread got me thinking about building my own system, and this hackaday looks almost exactly the thing https://savjee.be/2019/07/Home-Energy-Monitor-ESP32-CT-Sensor-Emonlib/

Looks like it would be really extensible.

[mavhc]

I can see from their website https://www.eastroneurope.com/products/view/sdm630mct-lorawan-mid that they have some LoRaWAN ones similar to the emon stuff, but it doesn't seem like they do base stations / gateways to go with them. Is there a standard for these sort of things?

 

Never used anything but wired, but LoRaWAN is a standard

 

https://www.eastroneurope.com/images/uploads/products/manuals/Eastron_Europe_SDM630MCT-LoraWAN_user_manual.pdf seems to have details

[LRSFC_DanJ]

Never used anything but wired

 

As mentioned, we're not looking to do a permanent installation at this time, this is just a pilot programme, therefore additional wiring for the monitoring stations would be out of scope for this stage of the project.

 

Ideally we just want to plonk a base station in some central location where it can be connected to existing network connections, and then have the monitoring devices communicate wirelessly with it. This will also allow us to move the monitoring equipment around and look at different areas should we choose to do so.

[mavhc]

I've never used anything but wired, therefore I don't know the LoRa stuff, probably worth phoning them though