Single-phase Equipment Connection Requirements And Automatic Voltage Regulator Capacity Matching Instructions

If the load includes single-phase equipment (such as 220V appliances), ensure a reliable neutral connection and that the single-phase load power does not exceed 1/3 of the 3 phase automatic voltage stabilizer capacity (e.g., a 100KVA voltage regulator with a single-phase load ≤ 30KW).

In practical engineering, when connecting single-phase equipment, a suitable grounding system should be configured to maintain potential balance between the neutral and ground wires, preventing unbalanced current from being generated by a single-phase load in a three-phase system. When using 50 kva automatic voltage stabilizer, capacity matching should be considered: for example, a 7.5 kva automatic voltage stabilizer rated at 100kVA has a theoretical single-phase output of approximately 100kVA ÷ √3 ≈ 57.7kW, but to meet the 1/3 limit, the single-phase load should be controlled within approximately 30kW.

If there are multiple single-phase devices in the system, their total single-phase power should be calculated together and evaluated against the rated capacity of a 7.5 kva single phase stabilizer. If the single-phase load exceeds 1/3 of the capacity, the ac automatic voltage stabilizer may operate near full load for extended periods, affecting its thermal stability and lifespan. In addition to the requirements for neutral wire connection and power matching, attention should also be paid to the peak starting current and load characteristics of single-phase equipment, because inertial or capacitive loads may momentarily exceed the rated current when starting, thereby temporarily increasing the impact on automatic servo voltage stabilizer.