ASP 15~18kW

Three Phase Low Voltage

Not necessarily. The ASP 15–18kW three phase solar inverter provides 120/208V output, so direct compatibility depends on the voltage requirements of the connected machinery. Some commercial equipment supports multiple operating voltages, while other machines require a specific supply. A motor rated exclusively for 480V cannot be connected directly to a 208V system without suitable voltage-conversion equipment. Equipment rated for 240V may also require further evaluation of its permitted voltage tolerance. Before selecting an inverter for a commercial facility, check the equipment nameplates and existing distribution standard. North American buildings may use 120/208V, 240V or 277/480V systems, which are not automatically interchangeable.

The ASP 15–18kW models specify up to 150% single-phase overload capability, providing additional flexibility when demand is distributed unevenly across the three phases. Consider a workshop operating three-phase machinery alongside lighting, portable tools and auxiliary equipment. Although the main machines may draw relatively balanced power, smaller single-phase circuits can create unequal loading during daily operation. When selecting a 3 phase inverter, engineers should examine the expected current on each phase rather than relying only on the facility's combined power demand. The 150% specification must be interpreted according to the manufacturer's permitted operating conditions and duration. It does not represent an additional 50% of continuous three-phase output capacity.

The 18kW model supports up to 28.8kW of PV input through two independent MPPT channels, each rated for a maximum of 14.4kW and 36A. The MPPT operating voltage range is 120–550V, while the maximum PV open-circuit voltage is 600V. For example, two roof sections with different orientations can be assigned to separate trackers. Each array can then operate according to its own sunlight conditions without requiring both sections to share one tracking point. In a commercial off grid solar system, string configuration should be calculated from the actual module specifications, including current, operating voltage and temperature-adjusted open-circuit voltage. The 28.8kW PV capacity provides additional solar energy collection potential but does not increase the inverter's continuous AC output beyond its rated power.

Simultaneous motor startup is possible only when the combined starting demand remains within the inverter's available short-duration output capability. The 18kW model specifies peak output of twice its rated power for 10 seconds. However, pumps, compressors and ventilation motors may draw several times their normal operating current during acceleration. For industrial backup power applications, motor starting methods, acceleration times and other equipment operating simultaneously should be considered together. Where the process allows, staggered startup sequences, soft starters or variable-frequency drives can reduce instantaneous power demand. This is particularly relevant to workshops where several machines may restart after an interruption.

The 16kW and 18kW models support maximum battery charging and discharging currents of 360A, while the 15kW version is rated at 320A. All three operate on a nominal 48V battery platform. At these current levels, DC distribution design becomes particularly important. Cable length, conductor sizing, busbar capacity, connection resistance and protective devices must be evaluated according to the actual operating conditions. For commercial backup power, battery capacity and discharge capability should be assessed separately. A battery bank may store sufficient energy for the desired runtime but still be unable to supply the required current if its BMS or individual modules have lower discharge limits. The selected configuration must support the expected operating current while remaining within the battery manufacturer's electrical and thermal limits.

Expanding from one 18kW inverter to six parallel units increases the combined nominal output capacity to 108kW. However, the larger system requires coordinated electrical infrastructure rather than simply adding more inverters. Parallel operation involves communication between units, suitable AC distribution, protection coordination and sufficient battery power. At higher output levels, the combined DC current demand becomes a major consideration in battery and conductor sizing. For a larger three-phase off grid solar system, planning the battery architecture, switchgear, equipment space and future load requirements before the initial installation can simplify later expansion. The 108kW rating represents the combined inverter output capacity. Sustained operation at that level still depends on the available solar generation, stored battery energy and overall system design.