Victron BlueSolar DUO PWM 20A Charge Controller

The Victron BlueSolar DUO PWM 20A Charge Controller charges two separate 12V or 24V banks from one solar array, with a programmable current ratio.

Charging two banks from one array is the point, and the programmable ratio is what makes it work sensibly. The available solar current can be divided between the banks rather than split evenly, so a house bank takes the bulk while a starting battery receives the trickle it actually needs.

PWM rather than MPPT is the technology, and it is simpler and cheaper but harvests less from the same panels. MPPT controllers track the array's most productive operating point; PWM does not. On a small installation the difference may not justify the cost, and on a larger one it will.

Programmable three-stage bulk, absorption and float charging manages recovery and maintenance. Twenty amps suits a modest array, and the dual-bank capability is what distinguishes this from a single-output controller of the same rating. Explore more solar charge controllers.

• Two banks from one array with an adjustable split
• House bank takes the bulk, starter takes a trickle
• PWM is simpler and cheaper than MPPT
• It harvests less from the same panels