question

geoffposkitt avatar image
geoffposkitt asked

Flash when connecting smart battery protect 65A

I am testing a bench setup with a smart battery protect. The load connected to the battery connect only draws 50mA and I understand the BP65 itself only draws a few mA. So why is there a quite large flash when I connect the 24v battery positive to the BP65 IN terminal? It all works fine but concerned about this apparent cuurent surge.

Battery Protect
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2 Answers
Alexandra avatar image
Alexandra answered ·

The the BP not connected to anything at this point - no loads/circuit?

With an always on battery the use of a pre charge resistor when connecting to a system.is always recommended.

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geoffposkitt avatar image
geoffposkitt answered ·

Actually I am using the BP purely as a monitor of the battery. So the only "load" I have is a relay taking 50mA. This relay will drop when the battery voltage goes below the programmed threshold. The real load is connected directly to the battery. This is a mission critical application that may not be disconnected even to protect the battery. So the relay being disconnected by the BP is an early indication of battery or charger failure. So in answer to your question 50mA for the relay is the only load. Can you please explain about the precharge resistor. Since the BP is only for monitoring, should I connect it to the battery via a 10ohm resistor??

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