I have a VPhase (http://www.vphase.co.uk/ - sadly I think now going out of business) 220vac voltage optimiser at home that feeds most circuits, excluding all higher power devices; Cooker, Electric Showers etc. with the aim of reducing power consumption during use and standby of the lower power, non-heating, devices. Reduced brightness of our reducing number of incandescent bulbs (not sure about our CFLs) is rewarded by longer life but the kettle which is on the ring main will take slightly longer to boil unless the VPhase goes into bypass mode at 8A continuous. Our mains line voltage is typically 253vac in a rural location. We also have 4kWp of PV.
My question is: can the EmonTx monitor two voltages by using one of the spare (but not brought out to a connector) analogue inputs?
I'm assuming that EmonLib only supports one voltage Vrms. Am I correct?
In the future I would like to monitor the 220vac output, as well as the currently monitored ~250vac line, of the VPhase so I can see when it goes in to bypass mode.
Thanks,
Steve
VPhase Specification Reference
http://www.allecoenergy.co.uk/newsletter/images/Files/Website_Updates/VP...
Re: Can EmonTx v2.x Monitor Two Mains Voltages?
You'd need to replicate the circuitry of the existing voltage input and connect it somehow The emonTx V2 is certainly the easiest to add that functionality to via a header using one of the 2 spare analogue inputs. On the V3 PCB, it's slightly harder because although AI5 comes to the terminal block (normally dedicated to the temperature sensor), it's connected to Dig19 and you must ensure that is made high impedance. As you rightly point out, EmonLib does not have the capability to use two voltages, but with some not very extensive modifications, that could be added.