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muzzerb avatar image
muzzerb asked

Blue solar 75/15 no load output

110W PV, 110Ah lead acid battery,fully charged, and a small water pump connected via the load output of the blue solar 75/15 . When pump tries to come on, the blue solar immediately turns load off. The blue solar is meant to handle 15A via the load, yet the pump is only pulling 4A , and a startup spike of max 9A . When pump directly connected to battery pump works fine, except in that config I lose most of the blue solars battery monitoring functionality.

Why is the load not working . The battery when directly connected show maintaining voltage when pump running etc . When via load the app shows the volts dropping to 0 !

MPPT SmartSolar
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2 Answers
Matthias Lange - DE avatar image
Matthias Lange - DE answered ·

The inrush current of a motor is 5 to 10 times higher than the normal operating current. In your case at last 20A.

I guess the MPPT detects that as a short circuit.

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muzzerb avatar image muzzerb commented ·

Thanks , sounds plausible, though with a meter on the battery I don’t see any voltage drop, and any inrush current would be for milliseconds. Is there anyway to have a stand down period before the algorithms kick in ? Otherwise I’ve bought a dud , or overpaid for a regulator . I don’t want to set always on, as that defeats / negates the purpose of the battery health checks

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muzzerb avatar image muzzerb muzzerb commented ·

Even always on doesn’t help, assume some internal self protect check maybe.

Note the connection has a 15A fast break fuse , and that isn’t popping

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Fideri avatar image
Fideri answered ·

@MuzzerB

I don't know what kind of meter you have but some meters can measure inrush currents.

F.

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