Battery Charge and Drain Expectation

[twistr25]

My lithium set up has been working well, but I'm beginning to fear I still haven't gotten all the kinks worked out. I bought the attached battery monitor and I'm wondering if I just don't have the settings right. This is the link too, https://www.amazon.com/gp/product/B08V1VZNGH/, but I've been running the cart a decent amount, enough I would assume the battery is going down, but I see no reduction in the voltage. Sometimes it will flicker to 99mAh or 99%, but then goes back up. Good 15 minute ride around our neighborhood and no fluctuating lower. Anyone else have a similar monitor or have any suggestions? For the max and min setting they are at 100 and 0. Maybe the batteries are that bad a$$, but I feel like that's not the answer.

[Pat911]

That’s a clone of the very good Renogy 500A meter.

I’d say you’ve wired it incorrectly. Have you connected the current shunt to the battery negative and does all current going in and out of the battery pass THROUGH the current shunt?

This meter works by “counting” the amps in/out of the battery to give you a state of charge. It does not rely on voltage and the displayed voltage is just for information.

This is the diagram from the link you posted above.

A7CB53CB-D6ED-4354-AFEF-A67BD6036453.jpeg

[augiedoggy]

Originally Posted by Pat911

That’s a clone of the very good Renogy 500A meter.

I’d say you’ve wired it incorrectly. Have you connected the current shunt to the battery negative and does all current going in and out of the battery pass THROUGH the current shunt?

This meter works by “counting” the amps in/out of the battery to give you a state of charge. It does not rely on voltage and the displayed voltage is just for information.

This is the diagram from the link you posted above.

Attachment 235748

its not a clone... rebogy doesnt actually make anything, they buy thier products from various chinese manufacturers often in cases like their charge controllers and solar panels , they just rebrand existing products. I have some of thier stuff and the identical counterparts.

[twistr25]

Originally Posted by Pat911

That’s a clone of the very good Renogy 500A meter.

I’d say you’ve wired it incorrectly. Have you connected the current shunt to the battery negative and does all current going in and out of the battery pass THROUGH the current shunt?

This meter works by “counting” the amps in/out of the battery to give you a state of charge. It does not rely on voltage and the displayed voltage is just for information.

This is the diagram from the link you posted above.

Attachment 235748

Yes, it is connected with that shunt.

[augiedoggy]

What is wired to the battery directly? I believe you want both the loads and the charging voltage to go through the shunt to keep proper/accurate track of everything..

[Volt_Ampere]

Yes - only the shunt could be connected to battery negative. It looks like the charger negative is hooked to battery negative in that picture. That's not correct based on the schematic above. That would bypass the shunt during charging.

[twistr25]

Originally Posted by Volt_Ampere

Yes - only the shunt could be connected to battery negative. It looks like the charger negative is hooked to battery negative in that picture. That's not correct based on the schematic above. That would bypass the shunt during charging.

So I should just move those cables to another terminal?

[twistr25]

Originally Posted by Volt_Ampere

Yes - only the shunt could be connected to battery negative. It looks like the charger negative is hooked to battery negative in that picture. That's not correct based on the schematic above. That would bypass the shunt during charging.

Ooooh, I see it now, I need to move the charging negative to the other side of the shunt.

[Volt_Ampere]

Yup. That should improve things.

[Pat911]

Originally Posted by augiedoggy

its not a clone... rebogy doesnt actually make anything, they buy thier products from various chinese manufacturers often in cases like their charge controllers and solar panels , they just rebrand existing products. I have some of thier stuff and the identical counterparts.

Rebadged is a better word then.