Hi
First of all, Id like to thank the active admin and community for developing a fantastic bit of kit!
Now, a very newby question!
I have just installed a 4Kw PV system and I'm looking to educate the wife and use energy more efficiently.
I have a list of features that I'm struggling to put together...
Monitor 2x PV systems (Going to put another 4Kw on the front of the house in a couple of years time)
Monitoring of key circuits in the main DB to give displayed usage of monitored circuits.
Controlling of loads (Dishwasher and Washing Machine) if possible??
Dumping of any potentially exported energy to the immersion heater, flicker free.
I was thinking of putting a emonPi in the loft to monitor both PV systems with a 9v voltage reference, then using a emonTx v3 next to the main DB to monitor grid import/export, this leaves 3 other channels to monitor other circuits.
The question, can I control a triac from the emonTX in a non flicker mode?
Also the generation meter has fixed terminals for a pulsed output, can I wire this into a emonPi directly without the use of an opto pulse LED pickup?
Also several people mention that using the pulsed output gives a more accurate measurement, seeing as you can pick up class 1 meters for next to nothing, how many can you feed into a emonTX or emonPi?
Also can you use a voltage reference at one point and pass the information to other units within the house? I know there will be volt drop but only at a couple of volts.
The current transformers are a clip on, there are very bulky and take up loads of space within a DB, is there a non split current transformer that anybody have had any success with?
I also read that the 433Mhz network can get saturated which lead to corrupted data, can a hard wired twisted network be used?
Sorry for all the questions but I’m potentially spending £300 odd quid and the wife is going nuts as it is.
Regards
Dave
Re: The eMon Possibilities
"can I control a triac from the emonTX in a non flicker mode?"
Yes, Robin Emley has a sketch to do it (and his output stage works with just the opto-trigger changed for a free-firing one). But you'll need a hefty filter to meet the limits for the generation of harmonics.
"the generation meter has fixed terminals for a pulsed output, can I wire this into a emonPi directly without the use of an opto pulse LED pickup?"
Maybe - it depends on what is inside the meter.
"how many"
Only one, as it stands 'out of the box'.
"can you use a voltage reference"
Yes, provided all also share a common ground connection. It also implies you're powering all your emonTx V3s from external 5 V supplies.
"is there a non split current transformer"
You mean ring core - that's difficult, because most are designed for 0.333 V output, which is not suitable. Robin Emley uses this or this 20 A one from here.
"I also read that the 433Mhz network can get saturated which lead to corrupted data"
That's not very likely with only two emonTx's - do you have visions of many more emonTx's? Serial wired comms is done inside the emonPi - roughly like this. I don't know what you'd do with multiple devices.
Re: The eMon Possibilities
My Solar PV system gets installed next week. Just ordered my emonPi.
I already have a Kemo M028N power controller, and the PWM converer which I planned to connect to a Raspberry Pi, along wth three temperature probes for my immersion heater.
However, I'm now thinking I might hack an emonTH instead. It should be possible to tap into a PWM output to drive the controller. Then, either get the emonPi to tell the emonTH what it should be doing, or get the emonPi to broadcast the import/export/generation data in real-time, and let the emonTH decide what to do.
Re: The eMon Possibilities
Hi, we've been running an Emonshield system since installing 5kWp of panels with optimisers last February. (shortly to be upgraded to EmonPi) We're both retired, so try to use as much generated electricity as possible. The single most useful and educational part of the system for us is the EmonGLCD - highly recommended! When the EmonGLCD PCB was out ouf production I built a second one with an Arduino nano and a 20x4 LCD, now have one in the kitchen and one in the living room.
One other point - having a house with lots of 433MHz kit existing, I deliberately standardised the installation on 868MHz. Software radio (SDRsharp) running on a cheap USB TV tuner shows a scary amount of things at 433......
Best of luck