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20 Amp. Dual Battery Solar Controller

20 Amp. Dual Battery Solar Controller

Regular price $99.00 USD
Regular price Sale price $99.00 USD
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Shipping calculated at checkout.

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.

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

Not Sure How Many Solar Panels You Need?

Try our Power Consumption Worksheet.

Make a copy of the worksheet and update with your information.

Wiring Diagrams

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Federal Solar Tax Credits Extended!

Federal Solar Tax Credits Extended!

Good News for Solar Enthusiasts: Now Extended Through 2034!

The Inflation Reduction Act of 2022 has extended the Federal Solar Tax Credit (ITC), giving homeowners and boat owners even more incentive to go solar. This tax credit applies to your primary or secondary residence—including certain boats with living accommodations (head, galley, and bunk) registered in the U.S.

What You Need to Know

Tax Credit Rate:

  • 2022–2032: 30% of total system costs
  • 2033: 26% of total system costs
  • 2034: 22% of total system costs
  • After Jan. 1, 2035: 0%

Eligibility:
You can claim this credit if you’ve made energy-saving improvements to your home (or qualifying boat) in the U.S. during the tax year. Qualified residences include:

  • Houses
  • Mobile homes
  • Condominiums
  • Cooperative apartments
  • Houseboats (with proper accommodations)

What’s Covered:
The credit applies to the cost of:

  • Solar panels
  • Batteries
  • Inverters
  • Charge controllers
  • Wiring and labor costs

Retroactive Eligibility:
Systems placed in service after January 1, 2006, can qualify if the credit hasn’t already been claimed.

Unused Credits:
If your tax liability is lower than the credit, you can roll over unused amounts to future tax years.

How to Claim the Credit

  1. Complete IRS Form 5695:
    Download the form here. Make sure to use the latest version updated in January/February of the applicable tax year.
    Instructions for Form 5695.
  2. File with IRS Form 1040:
    The total from Form 5695 is entered as a line item on Form 1040. Attach both forms when filing your return.
    Download IRS Form 1040.

Additional State Incentives

Many states offer additional tax incentives or rebates for solar energy systems. Check out the Database of State Incentives for Renewables & Efficiency (DSIRE) for a detailed breakdown of state-specific programs.

State Highlights

  • Arizona: 25% tax credit, up to $1,000.
  • Hawaii: 35% tax credit, up to $5,000.
  • New York: 25% tax credit, up to $5,000.
  • Oregon: Up to $6,000 in credits over four years.
  • South Carolina: 25% tax credit for installation costs.

Note: State programs are subject to change. Always verify details with your state’s tax department.

Don’t Wait—Take Advantage of Solar Savings!

With the credit extended through 2034 and now covering batteries, it’s the perfect time to upgrade or install a solar system. Be sure to consult your tax advisor to maximize your savings and ensure compliance with the latest regulations.

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Premium Marine Solar Panels/Systems and Lithium Iron Batteries

Improve your cruising experience with the highest efficiency solar panels available. 

  • Shipping

    Products ship day after payment domestically. International takes longer. We do not add tariff charges.

  • Custom Designs

    Our engineers will work with you to design a solar system specific to your needs including Lithium Batteries if you like. (Batteries are 10% off w/ solar system purchase).

  • Doug Heath - Santa Fe, NM

    Customer Service and Product

    Very pleased with the performance of the rigid solar panels purchased in 2022. Customer service also has been consistently excellent both before the sale regarding product selection and after the sale regarding installation and maintenance concerns.

  • William Roth - Kodiak, AK

    Heavy Duty Panels For The Win
    Installed 1200watts of panels on my 56' commercial fishing boat in Kodiak Alaska, with salt spray and harsh winters I hardly run my genset. Installation was a breeze with using silicone to mount them. Most the boats in my family fleet have them now and we are all saving big on the fuel bill! Couldn't be happier with the purchace.

  • Hartwell C - Bellingham, WA

    Easy Install - Great Performance

    I worked with Tom last year to design a system for my sailboat; the dialog and information was very detailed and helpful in helping determine my system needs and completing the installation. Once ordering, the kit arrived in a timely manner and very complete. The install was very straightforward and Tom provided additional information as needed. After the install I took off on a 7 month cruise of British Columbia. The system worked perfectly during my trip. I’m very happy with the equipment and support from CMP and Tom. I highly recommend !

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