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Connecting more than one charge controller to the same battery bank ?

Chadd

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Connecting more than one charge controller to the same battery bank ?

The Epever website says : -


Not recommended. the battery voltage that every controller detected has a minor difference. When the battery is nearly full, it is possible that some controllers are charging, and others not, or some are charging with a big current and others are charging with a small current.


However multiple other people say no problem, as long as both charge controllers are set up the same.

One did say : -

There might be a problem with flooded lead-acid batteries where they equalize every month. If you have multiple charge controllers attached to the battery bank they equalize more frequently, Which is not good for the battery. You need to turn off the equalizing function on the other charge controllers so you only have one charge controller performing the equalize function.

At the moment we have an Epever 30 amp charge controller and a 190 watt panel, feeding two 75amp lead acid batters and 3000w 12 volt inverter.

The four new panels on order are 340w - Luxor - mono crystalline.

As we look at it we need two 40 amp Epever charge controllers to handle two panels each.

The old 30 amp Epever charge controller will remain connected to the original 190 w panel.

I will then be able, I hope subject to learned advice, connect all three charge controllers to the 12 volt battery bank ?

I ask for advice as there are conflicting opinions, : )

As a by product, I have thought out a way of mounting the panels to balcony railings securly, making use of a ready made item and for little money.

As soon as I have contructed the devices I will post with pictures, they are aluminium and strong due to their construction : )

God Bless Chadd

 
Thank you kindly for the link, I shall order two 40 amp chargers and get the wiring ready : )

God Bless Chadd
 
I have 3 SCCs. The Victron’s network together for Bluetooth. When I had lead acid and hit equalize, all three went to equalize at the same time. I am also set up to flip a breaker to prevent input to any of the three SCCs
 
I have 3 SCCs. The Victron’s network together for Bluetooth. When I had lead acid and hit equalize, all three went to equalize at the same time. I am also set up to flip a breaker to prevent input to any of the three SCCs
Good morning thank you for your reply.

I have a breaker in the one panel we are running at the moment and will be adding one to the four new panels when installed.

I thought this was necessary if only to disconnect the panels if the batteries have to be disconnected as, I read this is the correct procedure ?

Did all three trying to equalize at the same time cause any problems ?

God Bless Chadd
 
Multiple charge sources can always be connected to a battery provided each is compatible with the battery. You can’t control which charger might take over a given load but if that’s not important it doesn’t matter. ( you can trick with the settings to try and prioritise ) as each charger hits its maximum the others will then share the load ( not equally but that doesn’t matter )

Nor does it matter if you force one charger into equalise mode. Charger are power sources not power sinks.
 
Good morning thank you for your reply.

I have a breaker in the one panel we are running at the moment and will be adding one to the four new panels when installed.

I thought this was necessary if only to disconnect the panels if the batteries have to be disconnected as, I read this is the correct procedure ?
That is correct. I store the RV and disconnect the batteries if it will be in storage for a bit.
Did all three trying to equalize at the same time cause any problems ?
No problems at all but the Victron are networked to work together for whatever they are doing whether its bulk, absorb, float, or equalize.
 
That is correct. I store the RV and disconnect the batteries if it will be in storage for a bit.

No problems at all but the Victron are networked to work together for whatever they are doing whether its bulk, absorb, float, or equalize.
Indeed they do. But it doesn’t damage anything if only one scc goes into equalisation mode, I have four charges sources connected to one bank on my boat.
 
Indeed they do. But it doesn’t damage anything if only one scc goes into equalisation mode, I have four charges sources connected to one bank on my boat.

I think the implication is that if you have multiple SCC, you don't want them all running EQ on a schedule as you might get multiple EQ in a 30 day period rather than the desired single EQ event in 30 days.
 
Multiple charge sources can always be connected to a battery provided each is compatible with the battery. You can’t control which charger might take over a given load but if that’s not important it doesn’t matter. ( you can trick with the settings to try and prioritise ) as each charger hits its maximum the others will then share the load ( not equally but that doesn’t matter )

Nor does it matter if you force one charger into equalise mode. Charger are power sources not power sinks.
I feel I understand it better now, I tended to think as I have read others do, that the panels pushed out power.

Rather it is power on demand is that correct ?

It certainly is a very interesting subject, there being far more to it all than I thought.

I have been in the repair side of radio and TV since 1961, there is even a early family BW photo of me in a nappy playing with a BT connecting box.

And yet still loads to learn. : )
 
If the equalization is only limited to one or they are synced it shouldn't be an issue.

If you're filling up a tub of water, the other hose doesn't know that the other hose is also on.

They fill up the tub. And turn off when full
 
There have been issues with mult.iple EPEVER SCC connected to one bank. They get stuck and panel voltage just above batt voltage and dont track out of it. See this thread;


I have had the same issue once with only one SCC hooked up. Disconnecting and reconnecting the string fixed it. It seems to happen during low light changes. It may have gotten a surface charge feedback from the batts and thought it was done charging.

A simple diode on the output could fix it or likely software updated. I don't think EPEVER even knows about the issue.

I currently have 7 victron 100/30 SCC hooked up in parallel with zero issues. I will expand it to 16 once I get my other mounts built
 
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