question

andyrlm avatar image
andyrlm asked

SmartSolar to charge LiFePo4 from gen + lead acid bank

There are similar questions to this on here, but mine is slightly different I think.

I would like to use a SmartSolar to charge a modest 24v LiFePo4 from a large lead acid traction battery, switched to operate when a 48v DC generator is charging the lead acid.

So it's a combination of 2 scenarios - as a charge controller on a DC generator, which I have seen some people report as having worked OK for them. The only problems I've heard are if the generator output is not sufficiently smoothed or spike-free, but mine would always be coupled to a 48v battery so this wouldn't be an issue. The voltage the SmartSolar would see would always be well within its PV voltage limit, and well above the voltage of the battery being charged.

However, the SmartSolar manual says: "Connecting a battery to the PV terminals can, under certain operational conditions, cause damage to the solar charger. This damage is not covered by warranty."

Does anyone know what conditions could cause damage? I can only think of reversed battery polarity creating a high short circuit current, and I'd just have to be careful to avoid that. Otherwise, I can only think that the SmartSolar would be seeing an input voltage that is varying within expected limits.

Can anyone foresee any other problems? Many thanks.

MPPT Controllers
2 |3000

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

1 Answer
kevgermany avatar image
kevgermany answered ·

Apart from warranty issues and damage, the smart solar will charge continuously. Unless you install a physical switch on the input side.

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.

andyrlm avatar image andyrlm commented ·

Thanks for this. According to the datasheet, the SmartSolar can be turned on and off using on-board terminals. I would switch this using the ‘running’ relay on my genset, so it would only charge when the generator is running. Does that make sense?

0 Likes 0 ·