SunSaver Duo

Morningstar’s SunSaver Duo™ is an advanced PWM two battery controller for RV’s, caravans, boats and cottages. This product will charge two separate and isolated batteries at the same time, such as a “house” and an engine battery, based on user selectable priorities. The SunSaver Duo employs Morningstar’s legendary SunSaver controller technology, whose long-term track record for high reliability and improved battery charging is well-recognized in the solar industry.

An optional backlit remote meter can be purchased with this controller, and mounted in or on a wall, to display digital and pictorial status information about the solar power system. The SunSaver Duo is epoxy encapsulated for environmental protection, is user adjustable via DIP switch or connection to a personal computer, and has an optional remote temperature sensor.

“Love it…it was worth the extra money over other brands that seemed to be of lesser quality”


Models: SSD-25, SSD-25RM,

Specifications and Certifications by Model

Model SSD-25 SSD-25RM
Charge Rating 25 amps 25 amps
Max. PV Open Circuit Voltage (Voc) 30 volts 30 volts
Nominal Battery Voltage 12V 12V
Self Consumption 6 to 10 mA 6 to 15 mA
Battery Voltage Range 1-15V 1-15V
Voltage Accuracy 1.0% 1.0%
Operating Temperature Range -40 C to +45C -40 C to +45C
Warranty 5 Years 5 Years
Remote Meter included No Yes
CE and RoHS compliant Yes Yes
TAA compliant Yes Yes
Manufactured in a Certified ISO 9001 Facility Yes Yes
Key Features and Benefits
  • Dual Battery Charging Capability
    Solar charge current is shared between the two batteries based on a user selectable priority (house and vehicle for example). When one battery is fully charged, all of the charge current flows to the other battery. This eliminates the need for a second solar charging system and  isolation between the batteries.
  • User Adjustable
    Set parameters with on-board DIP switches or further customize with a PC using Morningstar MSView software.
  • Provides Useful Information
    The remote meter and LED’s display system status data and any system errors. Custom icons and back lighting make the meter easy to read and understand.
  • Lower Cost
    Two battery charging eliminates the added cost of two separate solar charging systems and the need for isolation between the batteries.
  • Easy to Install
    The controller is installed near the batteries using the clearly labeled large wire terminals. The remote meter may be mounted in the wall or on the wall using the included frame. Also includes the meter wiring with RJ-11 connector.
  • Longer Battery Life
    Four stage series PWM pulse charging and temperature compensation increases the useful life of the batteries.
  • Extensive Electronic Protections
    The controller will not be damaged by wiring mistakes during installation. There are no fuses to replace, and the controller will automatically re-set after a wiring mistake.
  • Highly Reliable
    Epoxy encapsulation protects the controller against dust and high humidity. Efficient electronics and a conservative thermal design allow the controller to operate reliably at high temperatures. Five year warranty and estimated 15 year life.