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How to Use Your SolarFlex 1200i-L System


The SolarFlex 1200i-L system uses solar panels to recharge your RV’s batteries and an inverter to supply 120-volt power when shore power is unavailable. To get started, turn on the coach battery disconnect, inverter disconnect, and inverter, then monitor battery charge and electrical demand throughout your stay.

This guide covers the SolarFlex 1200i-L package installed on equipped Montana fifth wheels. Check your installed equipment and system documentation before making changes.

What components are included in SolarFlex 1200i-L?

The package described here includes:

  • Four 300-watt solar panels: 1,200 watts of rated solar collection.
  • Two solar roof ports: Connections for the rooftop solar array.
  • Two 50-amp Victron SmartSolar MPPT charge controllers: Regulate solar charging.
  • Two 270Ah Dragonfly Energy GC3 lithium batteries: A combined rated capacity of 540Ah.
  • 3,000-watt Magnum hybrid inverter/charger: Supplies inverter power and charges batteries from a suitable AC source.
  • Victron SmartShunt: Monitors battery charge and current flow.
  • Victron Cerbo GX: Provides system monitoring and connectivity.

Key electrical components are located in the front storage compartment.

How do you turn on the system?

Follow the startup instructions for your installation:

  1. Turn on the coach battery disconnect. This enables the coach’s 12-volt supply.
  2. Turn on the inverter disconnect. This connects battery power to the inverter.
  3. Turn on the inverter using its controls. When shore power is unavailable, the inverter supplies 120-volt power to the connected circuits.

Turning on the inverter does not increase available battery capacity. Check the battery charge before operating appliances, particularly high-demand equipment.

How do you connect to VictronConnect?

Use the VictronConnect app to view compatible Victron components.

  • Enable Bluetooth and stand near the equipment.
  • Match the devices shown in the app to the identification labels on your system’s component plate.
  • Select the SmartShunt to view battery information or a SmartSolar controller to view solar charging information.

For the Cerbo GX, follow the guide’s QR-code or manual Wi-Fi connection instructions to access the Remote Console. Its local Wi-Fi access point provides access to system information; it does not provide internet service.

If a device does not appear, check Bluetooth, connection range, and system power first. Missing devices do not automatically mean the batteries are asleep. If battery protection has activated, follow the system-specific recovery procedure rather than improvising a reset.

What should you monitor while camping?

Watch these readings as you use the RV:

  • State of charge: The estimated percentage of battery capacity remaining.
  • Battery current: Whether energy is entering or leaving the batteries.
  • Estimated time remaining: A changing estimate based on current consumption.
  • Solar production: The power being collected under current conditions.

When connected to shore power, check the Magnum remote for charger status. A blinking charger indicator can mean standby, so an indicator alone does not confirm a fault. Follow the guide before changing inverter or charging settings. 

Can SolarFlex 1200i-L run the air conditioner?

The system can supply inverter power for air conditioning, but runtime depends on battery charge, solar production, air-conditioner demand, and other operating loads.

The panels replenish the batteries; the inverter converts battery power into the AC power used by the air conditioner. Solar production may not keep pace with consumption, so monitor battery levels and reduce other loads when needed.

The system’s power-management equipment may temporarily shed loads to stay within available power limits.

How can you improve solar collection?

Clouds, shade, debris, and changing sunlight affect solar output. When choosing a campsite, consider how trees and nearby structures will shade the roof throughout the day.

Keep panels clean using water and a soft cloth or sponge. Let hot panels cool before cleaning, and follow the panel manufacturer’s instructions for approved products and safe access.

How should you prepare the system for storage?

Follow the storage instructions for your installed batteries and SolarFlex equipment. Confirm:

  • The required battery charge level
  • The inverter and disconnect positions
  • Whether solar charging will remain connected
  • Any temperature restrictions or battery-heater requirements

Leaving solar connected only helps maintain charge when the panels receive sufficient sunlight. Check battery condition during storage rather than assuming charging will always meet demand.

Where can you find detailed operating instructions?

Keep these system-specific resources available:

Review your system readings before your next off-grid stay to plan power use around your available battery charge.

Disclaimer: The information contained in this article is deemed to be true and accurate at the time of publication. However, due to the evolving nature of our products and services, there may be changes or updates that occur after this article was published. We encourage users to verify the contents and consult with their dealer or Keystone RV for the most current information. If you have any questions or require further clarification, please do not hesitate to contact your dealer or reach out to Keystone RV directly.