EmonBase vs EmonPi

Oan_De_Waal · 2019-12-03T09:26:22.017Z

Dear community

I was wondering what the main driver is for the price difference between these two base stations: EmonBase and EmonPi. I have gone through the technical documents but still, I struggle to understand the fundamental differences from a system design perspective and why there is such a big difference in cost?

I know the main characteristics are:
EmonBase: WiFi (2.4GHz), Radio wave connectivity (433 MHz), Raspberry Pi based.
EmonPi: WiFi (2.4GHz), Raspberry Pi based, LCD Screen, 2x CT ports

Costs
EmonBase: £57
EmonPi: £175 (That is 3 times the price)

I am not an expert, but I fail to see why one would buy the EmonPi rather than the EmonBase.

What I plan to do is connect 2 x IoTaWat devices to a network with 25 CT’s connected to upload data to EmonCMS to be accessed via the internet as well as via a local server.

Any comments would be greatly appreciated.

borpin · 2019-12-03T10:33:48.065Z

An EmonPi is an EmonBase and an EmonTX rolled into one. On it’s own, the EmonBase does not measure energy (note CT ports on EmonPi).

Oan_De_Waal:

EmonPi: WiFi (2.4GHz), Raspberry Pi based, LCD Screen, 2x CT ports

Oan_De_Waal:

What I plan to do is connect 2 x IoTaWat devices to a network with 25 CT’s

All you need is a Raspberry Pi and EmonCMS as the IoTaWatt does not communicate by RFM (IIRC).

Bill.Thomson · 2019-12-03T12:35:31.226Z

borpin:

the IoTaWatt does not communicate by RFM

Although it doesn’t use a radio module made by Hope RF, it does use RF.
In this case, Wi-Fi. In essence, 2.4 GHz instead of 433 MHz.
So, maybe a semantic thing of Wi-Fi vice UHF radio

Oan_De_Waal · 2019-12-05T20:30:34.564Z

Great, thanks for the feedback - it makes sense. What I don’t get is that the “value add” of 2x CT ports in essence would make the station increase in price three fold.

What else might I be overlooking? Maybe the emonPi has more feateres?

pb66 · 2019-12-05T21:40:30.734Z

An emonpi is a RPi and 2x CT monitor front end with rfm (incl external antenna), RJ-45 for 1-wire and pulse counter all contained in a single custom aluminium case with a LCD display,. An emonbase is just a RPi in a generic plastic case with a small rfm receiver.

The emonpi is a more elegant single unit solution if you only need 2 CT’s, but yes the emonbase is indeed more cost effective when used with an emontx (either via serial or rfm) as you have 4 ct’s and RJ-45 for 1-wire and pulsecounting, for less money, but it’s less pretty. IMO this is not an issue if you are locating it near the consumer unit ie in a garage or under the stairs etc.

Greebo · 2019-12-05T21:47:28.043Z

pb66:

An emonbase is just a RPi in a generic plastic case with a small rfm receiver

You don’t get the generic plastic case at the £57 price point.

Oan_De_Waal · 2019-12-06T16:19:21.395Z

Perfect, thanks for clarifying!