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jonathanv avatar image
jonathanv asked

Battery Protect for charge protection - what happens if there is a short circuit on the IN side?

When configuring a Battery Protect as a charge control device (as defined in the manual for Lithium setups), the chargers are on the IN side and the battery is on the OUT side.

What would happen if there is a short circuit on the IN side? Would this cause current to flow the wrong direction through the BP, frying it? Or would the short circuit protection normally meant for the OUT side also protect it?

screenshot-2023-05-05-134351.png



Lithium BatteryBattery Protect
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klim8skeptic avatar image
klim8skeptic answered ·

Fusing as shown in the diagram come into action and pop.

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jonathanv avatar image jonathanv commented ·
But those fuses will take some time to pop, they are 60A and 125A fuses on a BP220 in my case. In the meantime there's current going through the wrong direction?
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klim8skeptic avatar image klim8skeptic ♦ jonathanv commented ·
That is a better question.

As always, fusing is there to protect the cabling, not the equipment.

Fusing has to be rated to protect the cables they are protecting, and located as close to the battery side of the cable as possible. Look at the diagram.

A short on a 60a fuse (with appropriate cable and lithium batt) will pop it instantly.

As to whether the SBP survives this does not matter. As long as there is no fire, you survive.



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jonathanv avatar image jonathanv klim8skeptic ♦ commented ·

Yes, everything is fused to protect the cables as per the diagram, that's not the question. The original question is what would happen to the BP. It does matter to me and that's the whole point of this question.

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