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Fortress Power FlexTower All-in-One Energy Storage System

Save $774.00
Original Price $2,899.00
Current Price $2,125.00

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The FlexTower is an all-in-one energy storage system. Built on the foundation of the DuraRack battery cabinet, the FlexTower combines the battery, charge controller, and inverter into a single unit with an LCD control panel, and remote monitoring capability. The FlexTower is easy to install and carries IP65/NEMA3R ratings for indoor or outdoor use.

All-in-One Solution

  • Inverter, charge controller, LCD Control Panel, Battery and remote monitoring app integrated in one unit
  • Supports Off-grid, Back-up, Zero Export, Time-of-Use, Demand Response, Peak Shaving, and Virtual Power Plant

Flexible & Easy Install

  • IP65 water and dust proof for indoor & outdoor installation. NEMA3R
  • AC or DC couple to existing or new PV arrays
  • Optional Rapid Shutdown Button Included
  • Side knockouts sized for solar, grid, and generator wiring

Highest Reliability for Maximal Protection

  • 8000+ cycle life with tier 1 Automotive Lithium Iron Phosphate (LFP) battery
  • Easily scaled to meet all large residential and commercial electricity needs

Whole Home Backup with 200A Grid Pass-through

  • 200A Pass-through eliminates backup panel requirement
  • Saves time on inverter wiring
  • Includes battery cables and combiner for additional savings

Highest Roundtrip Efficiency to Maximize Your Solar Investment

  • >98% Battery Efficiency
  • 5% CEC-Rated Inverter Efficiency
  • Compatible with Din-Rail Heaters to maximize lifecycles in cold climates

DuraRack Specifications:

 Enclosure Material Carbon Steel
Enclosure Protection IP65 water and dust proven (outdoor)
Enclosure Color White
Dimensions [W x H x D] 29.29 x 41.34 x 18.03 in (744 x 1050 x 458 mm)
Enclosure Weight 59.6 kg / 153.2 lbs
Maximum Battery Units 4 eFlex 5.4
Storage Capacity Range 5.4kWh - 21.6 kWh per unit
Max. Storage Capacity 81 kWh (4 unites in parallel)
Knockout Size 1inch & 2 inch
Positive and Negative Battery Busbars 2 x 4 points; M8 (5/16) Terminal Rings
Positive and Negative Busbars to Inveter 2 points; m10 (3/8) Terminal Rings
Battery Cables 4 sets of
Terminal Torque 7.0 - 7.7 Nm (5.1 - 5.7 ft-lb)
Enclosure Warranty 3 Years
Certifications UL9540, UL9540A, UL1973, CEC, SGIP

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