BigBattery APEX-10K Off-Grid Inverter, 48V All-in-One Inverter with 11kW Solar Input and up to 200A Battery Charging, UL 1741

About the BigBattery APEX-10K Hybrid Inverter

The APEX-10K combines a 10kW inverter, dual MPPT solar charge controller, and 200A battery charger in a single wall-mounted unit. It outputs 120/240V split-phase pure sine wave power from a 48V battery bank, with a 20kVA surge rating that handles well pumps, compressors, and motor startup loads up to 6 HP. The pure sine wave output is equally clean for sensitive electronics, networking equipment, and audio gear.

UL 1741 certified, so permitting for battery-based power systems in most US jurisdictions is straightforward. Current Connected pre-configures every APEX-10K before shipment to your battery and system specifications, so it arrives ready to wire.

Dual MPPT Solar Input

Two independent MPPT trackers accept up to 10,500W of combined PV input (5,000W on MPPT 1 and 5,500W on MPPT 2). Each tracker operates independently with a 125-450Vdc MPPT range and 550Vdc maximum open-circuit voltage, so you can run strings at different orientations or panel counts without one tracker affecting the other. Maximum input current is 22A per MPPT. The combined solar charge rate maxes out at 200A to the battery bank.

Four Output Priority Modes

The APEX-10K gives you four configurable priority modes that determine how the inverter sources power and manages charging:

UTI (Grid First): Grid powers the load whenever available. PV supplements the grid and charges the battery. The battery only discharges when the grid drops out. This is the default mode.

SBU (Inverter First): PV and battery power the load first. The grid only kicks in when battery voltage drops below your configured threshold. When the battery recovers, it switches back to inverter output. This maximizes battery cycling and solar self-consumption.

SOL (Solar First): PV powers the load first. If PV is insufficient, the grid supplements without discharging the battery. This preserves battery capacity while maximizing direct solar use.

SUB (Solar/Battery Priority with Grid Charging): Solar charges the battery and powers loads. Grid charges the battery when solar is insufficient but only powers loads when both solar and battery are exhausted. Battery discharges only when the grid is unavailable.

Grid and Generator Input

A single AC input accepts either grid power or a generator (not simultaneously). The 120A maximum charge current from the AC input recharges batteries quickly when solar isn't available. The 45-65Hz input frequency range accommodates portable generator frequency drift. PowerControl limits the total AC input draw to whatever you configure, preventing generator overload.

The dry contact port supports remote generator start/stop. When battery voltage drops to your configured threshold, the relay closes to signal a compatible two-wire start equipped generator to start. When the battery recovers, the relay opens and the generator shuts down. No manual intervention required.

Timed Charge and Discharge Scheduling

Three configurable time windows let you schedule when the grid charges the battery and when the battery discharges to loads. For installations with time-of-use utility rates, this means charging from the grid during off-peak hours and discharging during peak pricing. Each of the three charge periods and three discharge periods is independently configurable down to the minute.

Parallel and Split-Phase Configurations

A single APEX-10K outputs 120/240V split-phase from one unit (L1 and L2 at 180° phase offset). For more capacity, up to 6 units parallel together using DB15 communication cables. Two units can also be configured as a two-phase system, and three or more units support full three-phase output for commercial applications.

All parallel units must share the same battery bank. Each unit's PV array must be independent (no shared strings between units). The parallel communication cables are included in the box.

BMS Communication and Battery Compatibility

The APEX-10K works with 48V lithium (LiFePO4 and ternary) and lead-acid batteries (sealed, gel, flooded). For lithium batteries with CAN or RS485 BMS communication, the inverter supports multiple protocols: Pylontech, PACE, Dyness, SRNE, Sunwoda, Ruida, Aoguan, Oliter, and Vilion. When BMS communication is active, the battery's real-time charge and discharge limits override the inverter's programmed voltage setpoints, giving the BMS direct control over the system.

Without BMS communication, the inverter operates in voltage-controlled mode using manually configured charge parameters. This works, but CAN or RS485 communication is strongly recommended for lithium systems to get real SOC reporting and dynamic current limiting.

BigBattery's own ETHOS, NEXUS, and HUSKY 2 INV batteries communicate with the APEX-10K over CAN for closed-loop BMS integration.

Installation Notes

The APEX-10K is IP20 rated, which means indoor installation only. Bottom-entry wiring keeps cable routing clean. The unit includes a removable insect-proof mesh over the ventilation openings that should be cleaned periodically in dusty environments to prevent heat buildup. Battery terminals use M8 studs with included SC50-8 and SC95-8 copper lugs. AC and PV terminals are screw-type with ferrule sleeves (ferrules to be provided by the installer).