Frequently Asked Question

How does the BRAT decide when to Charge?
Last Updated 4 years ago

The Brat waits until 110% of battery voltage is available open-circuit at the PV input. This is done to reduce hiccuping between charging and not charging and also because there's very little power available when the open circuit voltage is near battery voltage.

Using a power supply is not a true test in this case. Also, there 's a 10 second delay before it starts charging and voltage filtering, so the actual threshold was lower than 34v. It just appears higher because you were increasing the voltage.

The Brat transitions to lower power modes when not charging. Some margin above battery voltage is also meant to guard against The Brat uselessly 'charging' a battery while acting as a larger load than the panel can provide.

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