Multiple configuration on multiplus genset charge option

DIY
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Hello all!

I’m about to install a pv array with battery storage due to grid problems in my home.

Although a multiplus II 5000kva could suffice, I’ve gone on the safe side and I’ve got 2 5000s set up in parallel.

My first pv array during the winter will not be sufficient so I’ll have to use/charge from the grid or a 5kva generator.

If there a quick and easy way to change the power in limit for Grid or genset? The grid has about 3.5kW limit and the generator has the 5k.

I have a Cerbo S GX and its relay outputs and digital inputs are still available.

I already have set up a couple of contractors for selecting the grid/generator inputs.

I’m a full newbie on the cerbo programming for any functions… Its been a ruff few weeks and I only got the power cables a couple of days ago so it’s all un-done yet

I’m just collecting information on the details here and there. I’ll be sure to post my system and set-up when I get it wired in

(I’ll have tome for testing from the start since I still have to correct the house breaker panels - I’ll just have the hot water, my PC and well pump while testing)

I’ve read a little bit on the red node programming for bat SOC and charge on demand… I’m not sure of its the way to go.

I also have a PLC that will control a few water, power usage and other systems.
It could activate the grid charging if I can have a ‘low bat’ signal out of the cerbo or something.

Any input will be useful on the multiple automatic configuration if it’s possible.

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and noting came up so I’m not sure if I was not clear about something and I’m surely going to need some time testing the thing out

3

I think this is what you are after. All the really useful stuff is locked from node-red programming. See if this is applicable.

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The same setting is probably fine for both the grid and generator (assuming it doesn’t put out a dirty sine wave)
You will never pull 5kVa from a 5kVa generator.
They are rated at sea level (so factor in de rating for altitude) and usually don’t want more than an 80% load anyway.

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I’ll have a read about this further. I’ve seen node red so this could help out.

thank you

7

I’ve never load tested the generator but I’m pretty sure I’ll never load it to full. If I ever need to use it for recharging bats is would be at a lower setting but not as low at the grid connection.

my grid connection will have to support my sisters mini-house (heating mainly) and its a 3.45kW line… I would probably can pull 2kW from it maybe just 1.5kW. as for the generator I could pull a “little” more.
(after testing further I can be sure and will probably add force cooling on it for long use sessions)

I’m pretty near sea level. 120/200 Meters higher or something like it. it should pull about 4Kw out of it fine…

thank you :slight_smile:

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Ok. Well then also be aware that not loading the generator enough is also bad for it.
You will definitely need to experiment balancing two households. :+1:

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yes. its a gasoline model. I’ll have to load test it and try to see. I’m expecting to pull a little under 4kW out of it and see how it actually behaves.

I’m going to have a read on the transfer switch thingy on github ^^

edit: /typo…