Sunday, September 12, 2010

Use the Current Cost ENVI to determine if your transformerless solar inverter is using power after dark

We’ve recently had a few reports of “faulty” ENVIs, whereby people are reporting power readings from their solar panels on the ENVI after dark.

One of our customers thought initially that it could be power being generated by moonlight!

In actual fact, it appears that the inverter is drawing power after dark, typically 70-90W, but occasionally spiking to over 200W.

The reaction from the solar inverter manufacturers has been that the ENVI must be faulty, or it could be that the inverter is causing interference to the transmission. Naturally, we have been very worried about this, and have been working our socks of to work out what is going on. This included using a variety of different wireless electricity meters on the same circuit – they all agreed to within a couple of Watts, ruling out the interference suggestion.

Eventually, the answers have become clear. A Fluke Multimeter was reading 0.31 Amps being drawn after dark. A service engineer also reported a power draw of 300mA. 0.31A x 240V = 74.4 Watts.

This has been established in two cases so far, and in no cases have we received any evidence to show that the Current Cost ENVI is reading incorrectly. We’re not going to name the manufacturers involved here for liability reasons, and will continue to keep you posted with any new information we receive.

1 comment:

  1. I am glad to read your post!! pretty informative..thanks for providing such a nice post. Keep sharing more.

    solar inverter