Multiple Solar Panels on BMS

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Russell Lees about a years ago

I read how the BMS can handle multiple solar panels in an array, but what if they aren't in an array ? My situation is I have portable 85W solar panel with built in regulator, but I am reluctant to leave it connected when we are away from the camper. I am planning to permanently mount another smaller panel flat on top of the box on the trailer draw bar.

If the permanent panel was shaded and not generating much power, how should I connect the second (portable) panel that could be in full sun ?
Should I bypass the built in regulator on the portable panel to feed the BMS?
Do I need diodes on each panel to stop the high charging one feeding back into the low charging one ?

On another topic :

Does the BMS cut power to the load when the house battery voltage drops low ?

What are the cut out and reconnect voltages ? (concerned about fridge trying to start with low voltage causing rapid cut out cycling)

Dylan @ REDARC

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Hi Russell,

Firstly thanks for your inquiry. I, with a little help from our engineering team, have come up with some answers to your questions, please feel free to contact us should you need any more assistance.

Â· The solar panels can be connected in parallel to the BMS if the internal regulator of the regulated panel is bypassed.

Â· As for the blocking diodes they would be required if there are not already blocking diodes on the solar panels.

Â· The BMS does not cut loads when battery is getting low, it will cut its power when the 'start' battery gets low, but as the loads in a BMS setup are connected through the shunt directly to the battery (and not through the BMS itself), it won't cut the power to the loads only. To achieve this you could use either a SBI battery isolator or VS voltage sensor.

As i mentioned earlier, please feel free to contact us or reply to this post should you need any more info.