question

mark-ruijzenaars avatar image
mark-ruijzenaars asked

Marine solution grid feedback en ESS

Gents,


I have a question, and hope you can help me.


We have a boat and when we are in our marine we want to use the shore supply as less al possible. Normally there is not al lot of equipment online but always de Victron, a security camera, modem router and sometimes the refrigerator.


a: My idea is to only use the shore supply when de SOC of the battery is below a certain value and at night.

b: When the battery is full I want to use the solar energy to feed it back to the grid. (Is that possible with this DC connected MPPT converter via the Victron?)

c: When we are not in the marina and we are using the generator I what to switch to normal mode (no feed solar energy and charge the battery to the max).


Is there an assistant or multiple assistants that can do something like this?


We have the following components:

- Multiplus II 24/3000/70/32

- MPPT 100/30 (with 2 395wp solar panels)

- BMV712

- Digital control.

- 500Ah (C5) 24VDC flooded tubular plate battery.

- Generator. With 2 simple relais switching between shore supply and generator supply to the Victron.


Already thanks for jour creative solutions and options ;).

Multiplus-IIESSGenerator
2 |3000

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

4 Answers
Paul B avatar image
Paul B answered ·

you would need to add a venus device, I would recommend a Victron Cerbo unit, and then this can control your systems quite easly to do that. (the cerbo also gives you remote monitoring as well)

yes you have to add assistants etc and a bit of a learning curve.


2 |3000

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

mark-ruijzenaars avatar image
mark-ruijzenaars answered ·

Thanks!

Why the cerbo unit? The are different gx types, not sure what the exact diffence is....


Regards!


1 comment
2 |3000

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

jwfrary avatar image jwfrary commented ·

More processing capacity on the cerbo. - and inputs should you need them for tanks. etc. You could also use it to run a signal k server (But you need to use the 'large' install and its not a supported function by victron)

0 Likes 0 ·
Al avatar image
Al answered ·

I'm sorry to say I think although it is possible, it is not allowed.

ESS is not allowed for boats as we use plugged cables, not hard wired into the marina fuseboard, and if you unplug the cable the male contacts will still be live trying to backfeed your excess solar into the grid which is very dangerous to touch!

1 comment
2 |3000

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

mark-ruijzenaars avatar image mark-ruijzenaars commented ·

Dear Al,


Thanks fore the reply.

There fore I would like to implement via an external input tot change between ESS mode en "normal mode" (generator or Not shore supply).


Thanks.

0 Likes 0 ·
jwfrary avatar image
jwfrary answered ·

I had an idea, not yet actually implemented.

Using a GX device. and the generator stop/start relay on it.

Stick that gx relay into the multi plus inputs, and use that to trigger the AC Ignore function in the multi.

Ultimately the thresholds on the GX device tell the multi to accept/ignore the shore power. if you have a generator can also start that.

Using the quiet hours function you can change the thresholds for night time use.

All can be done without the use of ESS.

I have been holding off until I get around to fitting the solar panels to that system.

2 |3000

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