Rocksolar 3.5kW Off-Grid Solar Power System with 48V Battery Storage & 6×440W Panels

Off-Grid Solar Kit — 3.5 kW Inverter (SPF3500TL) + 48V 74Ah Battery + 6 × 440W Panels

Quick Overview

This turnkey off-grid kit pairs a 3.5 kW inverter (SPF3500TL) with a 48V 74Ah lithium battery and six 440W solar panels. It’s designed for cabins, RVs, small farm outbuildings, remote work sites, and backup power for homes. The kit balances solar generation, energy storage, and inverter capacity for reliable off-grid performance.

Core Components

• Inverter: SPF3500TL — 3.5 kW continuous output (pure sine wave recommended for sensitive electronics).
• Battery: 48V, 74Ah (48 × 74 = 3552 Wh nominal energy).
• Solar array: 6 × 440W panels = 2640 W nominal DC (6 × 440 = 2640).
• Recommended charge controller: MPPT, ≥ 60 A @ 48V (see calculations below).
• Mounting, cabling, fuses, breakers, and safety equipment included or specified per site.

Electrical & Energy Estimates (Example Calculations)