1. Basic architecture of off grid system
**Power generation unit * *: Photovoltaic array (with a super matched design of 150-200%)
**Energy storage core * *: high cycle lithium-ion battery pack
**Energy Management * *: Off grid dedicated inverter charging integrated machine
**Backup power source * *: diesel/gasoline generator (optional)
2. Key design parameters
Battery capacity: ≥ 3 times the daily average power consumption, note: Consider the number of autonomous days on rainy days
Discharge depth: 80% DoD (daily)/100% DoD (emergency), note: extends battery life
System voltage: 48V/96V/120V, note: Select according to load power
Charging efficiency: ≥ 95%, note: MPPT solar controller is essential

1. Characteristics of off grid dedicated batteries
**Ultra long cycle life * *: ≥ 6000 cycles @ 80% DoD (LiFePO4)
**Wide temperature range performance * *: -30 ℃~60 ℃ working range (with heating function)
**High rate discharge * *: continuous 1C, peak 3C (emergency scenario)
**Modular design * *: supports flexible expansion of 5kWh units
2. Special protective design
**Anti backflow protection * *: prevents reverse discharge of the battery at night
**Lightning protection design * *: 10/350 μ s lightning waveform protection
**Moisture proof treatment * *: Three proof paint coating (suitable for high humidity environments such as islands)

1. Home off grid system
**Load situation * *: Refrigerator (150W)+Lighting (200W)+TV (100W)+Water pump (800W)
**Configuration Plan * *: Photovoltaic: 3kWp (12 × 250W modules), Battery: 15kWh LiFePO4 (48V 300Ah), Inverter: 5kW Off grid type (including 80A MPPT)
**Autonomous days * *: 3 consecutive rainy days
2. Communication base station system
**Load situation * *: Communication equipment (1.5kW)+air conditioning (2kW)+monitoring (200W)
**Configuration plan * *: Photovoltaic: 10kWp (double-sided module), Battery: 60kWh high rate NMC (96V system), Inverter: 15kW industrial grade (with RS485 remote monitoring)
**Design standard * *: Meets Tier4 reliability level

1. Plan for high-altitude regions
**Battery heating system * *: -20 ℃ automatic start heating film, insulation layer+electric tracing design
**Optimization of Photovoltaic Modules: Choose low-temperature coefficient modules (-0.29%/℃) and increase the installation angle (latitude+15 °)
2. High salt spray plan for islands
**Anti corrosion treatment * *: 316L stainless steel shell, gold-plated connectors
**System reinforcement: anti typhoon structural design, anti wave splash installation height ≥ 2m

1. Core control functions
**Multi source coordinated control * *: prioritize photovoltaic power supply, supplement battery power supply, and finally start the generator
**Load classification management * *: critical loads (continuous power supply), secondary loads (automatic cut-off when low battery)
2. Remote monitoring solution
**4G/WiFi/Satellite * * Multimode Communication
**Cloud management platform * *: Real time display of power generation/consumption data, fault warning push, remote parameter setting

1. Special precautions for installation
**Battery installation * *: moisture-proof at a height of ≥ 30cm from the ground, with a spacing of ≥ 50cm between heat dissipation channels
**Cable requirements * *: DC side: photovoltaic special double insulated cable, AC side: flame-retardant copper core cable
2. Maintenance cycle table
Battery status inspection: cycle - monthly, inspection points - voltage balance, temperature
Fastener fastening: cycle - quarterly, inspection points - torque verification, anti-oxidation treatment
System performance testing: cycle - every six months, inspection points - charge and discharge capacity testing
Environmental adaptability inspection: cycle - annually, inspection points - sealing and anti-corrosion coating status