Dual Battery Bank Controllers

The PWM Duo Dual Output Controller is designed to charge two independent battery banks with customizable charging priorities. It features an advanced four-stage charging algorithm and supports various battery types. The controller includes options for an external backlit LCD display and a remote temperature sensor for optimized charging. It supports both 12V and 24V systems, with models available for 10A and 20A solar current. Pricing starts at $79 for the 10A model and $99 for the 20A model, with optional accessories available.

Dual Battery Bank Controller Advantages

Charging of two independent battery banks:

The owner can set charging priority between the two battery banks in steps of 10%. For example, you can decide that 90% of the solar current should go to the house battery and 10% to the start battery.  When one battery bank is full all the power is redirected to the other battery.

Battery optimized charging algorithms:

• Advanced PWM four stage algorithm with bulk, absorption, float and boost (equalization) charging.

• Charging voltages are optimized for the selected lead-acid battery type (liquid, sealed or gel).• Selectable PWM charging frequency (25, 50 or 100Hz)

• Temperature compensated charging using either a built-in temperature sensor or an optional remote sensor.

External display with charging data (option):

• External backlit LCD display can be mounted recessed or in a provided frame up to 10 m (33 ft) from the charge controller.

• Display shows charging voltage, actual current, max current and total amp-hours provided by the solar panels.

• Display shows current, minimum and maximum voltage of each battery bank as well as charge provided in amp-hours.

• Other information includes temperature, time, charge priority and frequency settings and troubleshooting information.

Dimensions:

• Charge controller: 6" x 3 1/16" x 1 3/8" (155 x 77 x 35 mm).   Weight 8.8 oz. (250 g) for 10A model, 10.6 oz. (300 g) for 20A model.

•  Remote display: Cutout hole if flush mounted: 3"(75 mm), face plate 3 3/4" x 3 3/4" x 5/16" .
Frame mounted dimensions 4 1/2" x 41/2" x 1 9/16" (112 x 112 x 40 mm). Weight 5.3 oz. (150 g)

Specifications - Controller:

  • For 12V and 24V systems (nominal voltage), automatically sensed. Charging voltages given below should be multiplied by 2 for 24V operation.
  • Max solar current 10 A  for smaller panels or 20 A  for larger panels (greater than 150 watts)
  • Absorption voltage 14.2V (sealed battery), 14.4V (flooded battery), 14.6V (industrial battery) or
  • Boost voltage 30 min 14.4V (sealed battery), 14.6V (flooded battery), 14.8V (industrial battery)
  • Float voltage 13.7V (all battery types)
  • Max intrinsic power use 4 mA at night, 10 mA when charging
  • Protected against short circuits, over-currents, reverse currents and lightning
  • Temperature range for use : from -35°C to +55°C
  • Temperature compensation -30 mV/°C
  • 4 mm2 (10-12 AWG) max wire size terminals to solar panel and batteries
  • 1.5 mm2 (16 AWG) terminals for optional remote temperature sensor
  • RJ45 connector for cable to optional remote display
  • IP22 ingression protection
  • Circuit protected against high humidity
  • Minimum operating voltage: 8 Volts

Wiring a Dual Output Solar Controller

  • A Typical Wiring Diagram for Charging Two Battery Banks Using Two Solar Panels and Our Dual Output Solar Controller

Remote Display

This optional remote display provides all the information you need to track the performance of your solar panel.  It is particularly useful when optimizing panel tilt using our top-of-pole mounting system. The display plugs into the Dual Bank Battery  Controller.Features include:

  • Monitors and Displays Solar Charge Rates
  • Monitors and Displays Condition and Charge of both Battery Banks.
  • Solar Charge shown in volts, amps, amp/hr. rate, and frequency rate.
  • Displays % of charge for both batteries.
  • Battery Charge shown in volts, volts min., volts max., and amp/hr. stored.
  • Displays both Battery Banks Separately.
  • Displays Time and Local Temp.
  • Optional  RTS Displays Battery Temp. and Adjusts Charge Rate.
  • Adjustable Backlighting
  • Adjustable Data Repeat.
  • 10 Meter Cable
  • RJ45 connector for cable to charge controller
  • Max intrinsic power use 17mA with no backlight, 20mA with low backlight and 23mA with bright backlight

Remote Temperature Sensor

The optional remote temperature sensor constantly measures and  displays storage battery temperature so the controller can adjust charge rate appropriately. This is especially important when using temperature sensitive gel batteries.  This option will increase battery life by 100-200 charge/dischargecycles.The sensor plugs into the Dual Bank Battery  Controller and is attached to the top of a battery in the battery bank with tape.

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What our Smartphone App Shows You.

Battery State of Charge %
Battery Voltage
Battery Amp Hours Remaining
Status: Standby, Charging. Discharging.
Condition: Perfect, Very Good, Good, Fair. Poor
Fault Codes: Over Voltage, Over Amp.
Number of Charge Cycles
Battery Temperature
Battery Cell Group Voltages
Time to Fully Charged

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