Small inverter used as ess system.

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Wayne asked Jun 11, '20

Small inverter used as ess system.

Hello, newbie here so please have patience

I've just acquired a used solar kit consisting of three 250w panels, a victron 12/1200/50 multiplus inverter, a victron mppt 100/30 and two large 6v rolls lead acid batteries for €300.

It was used in a small off grid setup which I was thinking of using to power my garage and caravan as it's already setup for that task.

But I was also thinking of using it in our main house which has grid connection?

If I used it in this situation could I use it as an ess setup? Using the batteries for evening usage and grid as backup or in the event of needing extra power from the grid when required?

I've read that I'd need a gx monitoring system to use ess and read that a raspberry pi can be used for this task as I already have one.

I think I'd need a usb to mppt cable and a MK3 usb cable.

I believe I'd also need the MK3 cable to setup the inverter for grid/ess usage.

My questions are:

Is it worth using this as an ess system in the house, it's a small system but we are low consumers.

Is there any other items I need apart from the mentioned cables, is a battery monitor required?

Thank you in advance

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Answer 1 · 2020-06-11T18:22:31Z

Alexandra answered · Jun 11, 2020 at 06:22 PM

@Wayne

I don't see why using the system as an ess system would not be worth it. It is big enough to power your fridge, lights and smaller appliances like TV or laptop.

We have a 3kva and our base load for lights TV, wifi, laptop and fridge is about 500W with the fridge running.

Saved one third of our power consumption using it with ess not running the batteries down in case of power outage which happens alot here.

You are on the right track in your research. And the items you need. The battery monitor is not entirely necessary at the internal SOC is pretty decent and the CCGX displays all you need. We added a BMV to our system but we have lithiums and wanted a way to cycle count and other features.

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Answer 2 · 2020-06-11T18:42:22Z

Wayne answered · Jun 11, 2020 at 06:42 PM

Thank you so much for your reply.

Yes I thought it would be worth doing and maybe upgrading later if required.

So I need to order a MK3 usb cable and a usb to mppt and then try the raspberry, or a proper GX controller such as a Venus?

Thank you so much.

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Answer 3 · 2020-06-13T11:21:00Z

Wayne answered · Jun 13, 2020 at 11:21 AM

Could I ask another question?

I'd be wiring the inverter parallel on the AC in connection on the inverter.

Is it essential to use an AC sensor in this setup?

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