After a search for different energy meters I went to buy this. I was attracted by two things:
1) Availability of a serial interface to read energy data with a PC or other hardware
2) Possibility to set a different Voltage than 240V, suitable for non-UK installations.
The unit works, but I have found major limitations that were not clear even by reading the PDF manual in advance, and that make me quite upset and dissatisfied.
First, the Voltage of the network can only be customised if you're connecting an S2-capable sensors to it. So if you're using C2-capable sensors you have to live with 240V calculations even if you're using it in a different network. Operating at 230V would typically introduce a 4% error on top of the existing measurement. The worst is that if you have a mixed set of sensors (C2 and S2 attached to the same EnviR unit), it would be harder to discriminate this additional error because it would not apply to all sensors, unless you leave the S2 sensors to 240V and then add 4% at the measure.
The second pain is related to the fact that the unit assumes that a single "house" sensor is available (on channel 0). In my case I have two separate electric circuits to measure and the enery meter is in the basement, too far to reach the EnviR. So I purchased an additional CT sensor and have connected the two CTs to each circuit. Then I expected the display unit to offer the ability to combine multiple sensors into a single energy measurement, but this is not the case. Each sensor is managed as an individual source on each "page" of the display (channels 1 to 9) and channel 0 is assumed to be a CT sensor attached right after a single energy meter.
I will now write my own software to compensate all these issues (Voltage and sensor schema), but this would make the EnviR display almost useless.