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ppy61 avatar image
ppy61 asked

Smart Solar 100/20 Connections

Hi guys, I purchased the 100/20 unit to replace a PWM solar charger in my motorhome. with a view to upgrading my solar panels at some point. NB> I have an Elddis Accordo 125 fitted with a BCA PDU (Power Distribution Unit).The Solar charger installation recommends that the 12V loads are connected to the (Load) terminals. which involves me breaking the connections between the PDU and the battery, effectively placing the charger in series between battery and PDU terminals.

My question : when the motorhome is on Electric Hook up -EHU-, the PDU has an inbuilt battery charger for the leisure battery, or, when driving the PDU charges the leisure battery using the van's alternator.

IF the Solar charger is wired as recommended (in series between PDU and Battery), will charging current flow from the PDU connections, into the (Load) terminations, then through the Solar charger and back into the battery via the (battery) terminals ? ie back feed to the battery through the Load terminals ?

Obviously I would not like to lose the PDU's battery charging function.

Van Wiring.pdf

MPPT SmartSolar
van-wiring.pdf (3.9 MiB)
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3 Answers
Matthias Lange - DE avatar image
Matthias Lange - DE answered ·

Using the load output of the MPPT is optional, you don't need to use it.

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regman54 avatar image
regman54 answered ·

According to the wiring diagram you provided the solar charge controller is wired directly to the battery. Why do you want to use the load terminal?

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ppy61 avatar image
ppy61 answered ·

thanks for comments guys, I'm aware that using the load terminals are optional. However according to the manual , if the load is connected to the unit load terminal, this allows the unit to better monitor and manage the battery status, using real information, also able to determine power flow out of the battery, and the unit can turn off the loads should voltages drop below battery damage levels.

I tried raising a question with Victron, but the web sends questions to suppliers sales staff fronting technical questions. Unfortunately these guys are more sales than technical.

All I wanted to find out is if the power flow can be bi-directional through the Load terminals because of the PDB managing the EHU & alternator charging.

My fall back position is to ignore the Load output terminals, so no real biggie, just a pity that Victron do not make a technical centre of excellence available to customers questioning..

Cheers...



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