Balance of system
Choose compatible, correctly rated balance-of-system parts with traceable certificates and warranty.
Grid inverters, hybrid inverters and MPPT controllers must match PV voltage window, current, string count, battery chemistry, communications and grid standard. Check efficiency curve, anti-islanding, IP rating, surge protection, monitoring and local service—not only headline kW.
Specify usable kWh, nominal voltage, chemistry, DoD, cycle condition, BMS protocol, continuous and surge current, enclosure and warranty throughput. Ah without voltage is incomplete. Lead-acid needs ventilation and maintenance; lithium needs compatible BMS communication and protective settings.
A complete system may require DC/AC isolators, fuses or MCB/MCCB, type-appropriate SPDs, earthing and lightning protection, UV-resistant cable, approved connectors, labels and emergency shutdown. Ratings follow fault level, voltage, current and SLD; a generic DB is not automatically safe.
Mounting structures must suit roof type, corrosion environment, wind and waterproofing. Monitoring should record generation, alarms and communication health. Keep serial numbers, torque records, test results, manuals and firmware settings for service.
Planning table
| Accessory | Selection key | Do not buy by |
|---|---|---|
| On-grid inverter | MPPT/string/grid compatibility | kW alone |
| Hybrid inverter | Battery protocol + surge | Marketing backup claim |
| Battery | Usable kWh + cycles + BMS | Ah alone |
| ACDB/DCDB | SLD + fault/protection study | Box size |
| Structure | Roof + wind + corrosion | kg alone |
Every accessory must be matched to the approved system design and manufacturer documentation.
SS Enterprises · Patna
Share the location, recent bill or hot-water demand, roof photographs and preferred timeline. We will identify the missing survey data before quoting.