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Maximum voltage on power inputs

I have a floathub module on the way to Australia. Before connecting the power inputs i have a question. In the documentation, it talks about solar panel voltage monitoring, yet in a pictoral drawing, it shows the connection to float hub on the output side, which means battery voltage monitoring. Since solar power would exceed floathub power voltage, would this cause a problem…or would a voltage divider from the solar be the way to go for the input? Second question. If i lose power to the float hub and still have power on the voltage monitoring inputs, do i need to fit a blocking diode to prevent this, or is there protection on the input circuits.? Looking forward to installing the unit.

On the first question, typical install on panels is to the output of the panel (or group of panels) . That way you can see the voltage at the panel as well as the separate voltage of the battery (which would be the same as the output side of the charge controller when the active). So you get data like this (for example, with green being the panel and blue the house bank):


The battery and charger inputs are ok for voltages up to about 25-26 volts. If you have a 24 volt system with any charge source going significantly above nominal 24 volts, then you would need to think about a voltage divider or other resister-type system to drop down that voltage before connection to FloatHub.

On the second question, you just need a fuse on the monitoring lines to handle overloads/spikes/short circuits. No diode is needed. The device will not draw any (substantial) power on the monitoring lines and would not be damaged by having no power on it’s DC input lines while having within spec voltage on its monitoring inputs.