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Based on the capacity of the electrical equipment in the workshop (in kilowatts), the magnitude of the current load is estimated (in amps), which serves as a basis for selecting the power supply circuit.

Power for equipment, lighting, and maintenance.

Based on the different types of process equipment in mechanical factory workshops, the corresponding estimated current is provided for every 100 kilowatts of equipment capacity. The mnemonic is empirical data on power distribution in different processing workshops of mechanical factories. Suitable for three-phase 380 volts. The load current in the workshop changes continuously during the production process. The calculation is generally complex. But only an approximate value can be obtained. Therefore, using mnemonics for estimation also has certain practical value and is relatively simple. To keep the method simple, the equipment capacity in kilowatts referred to in the mnemonic is calculated based solely on the electrical equipment used in the process (no need to distinguish between single-phase and three-phase systems, or between kilowatts and kVA when making the calculations). They can all be considered in kilowatts and added together). Some auxiliary electrical equipment such as ventilation fans, lighting, and cranes can be ignored, as there is already an appropriate margin in the estimated current to accommodate their power consumption. Sometimes, the statistical data already includes these auxiliary devices. There’s no need to force a deduction either. Because their participation or non-participation has little impact. The current estimated using the mnemonic is the current in a three-phase or three-phase four-wire power supply circuit.