question

ispookie666 avatar image
ispookie666 asked

ET340 and Solar

I have an existing 3.5KWp solar (enphase micro inverters since 2015). The excess is exported to the grid. The solar comes to the consumer unit via solar generation meter and an isolator. There is a MCB on the consumer unit for the solar feed.

I have setup a ESS using - Venus GX, Multiplus 48V to feed a critical load of 250-290W. I have an ET340. My consumer unit is far away from the Multiplus. If I wire things like the picture shown, would ET340 be of any good?

I want to be able to use the Excess solar to charge the Lithium batteries rather than export it.

Energy Meter
home-wiring.jpg (40.2 KiB)
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

1 Answer
wkirby avatar image
wkirby answered ·

The ET340 manual describes what you want to do with a detailed wiring diagram.

https://www.victronenergy.com/live/energy-meters:et340


Use the RS-485 - USB dongle to connect the ET340 to the Venus.

https://www.victronenergy.com/accessories/rs485%20to%20usb%20interface

5 comments
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

ispookie666 avatar image ispookie666 commented ·

I have seen the wiring, I was thinking of just using ET340 to track solar PV output and use it to charge the batteries also, the Output of ET340 would not be directly connected to the Multiplus (AC in for multiplus will be from a socket)

0 Likes 0 ·
ejrossouw avatar image ejrossouw ispookie666 commented ·

Not sure where in the world you are, but connecting a mutiplus to a socket (like a lamp etc) is not allowed. It it a power generator and bi-directional meaning if the plug is removed from the socket, it may be live and dangerous. Hopefully I misunderstood ;)

0 Likes 0 ·
ispookie666 avatar image ispookie666 ejrossouw commented ·

Excellent point. This is a temporary installation. I'm in the UK, as far as I know I don't need a separate anti-islanding device.

0 Likes 0 ·
ejrossouw avatar image ejrossouw ispookie666 commented ·

No need for anti-islanding device indeed, however don't forget to install a lockable isolation switch between your installation and the grid and to notify your DNO of the connection within 30 days of the installation under G98 or G99 as applicable ;)

0 Likes 0 ·
ispookie666 avatar image ispookie666 ejrossouw commented ·

This is getting even more complicated, best would be just round this thing up and sell the whole lot.

0 Likes 0 ·

Related Resources

Energy Meter Selection Guide