STUD 3N6192 - Caterpillar

Loading of the Generator
When a generator is installed or reconnected, be sure that the total current in one phase does not exceed the nameplate rating. Each phase should carry the same load. This allows the engine to work at the rated capacity. An electrical unbalance can result in an electrical overload and overheating if one-phase current exceeds the nameplate amperage.Allowable combinations of unbalanced loads are shown in Illustration 1. When you operate with significant single-phase loads, the combinations of single-phase load and three-phase load may be used. Such combinations should be located below the line on the graph.
Illustration 1 g00627416
Allowable Combinations of Unbalanced Loads
Block Loading
When an electrical load is applied to a generator set, block loading occurs. This load may be anywhere from a moderate percentage of the rated load up to the full rated load.The block loading capability of a generator set depends on the following factors:
Engine transient response
Voltage regulator response
Type of the voltage regulator
Altitude of operation of the generator set
Type of load
The amount of load that is already presentIf a block load rating is required, refer to ISO 8528 Standards or SAE J1349 Standards. Also, reference Engine Data Sheet, LEKX4066, "Block Loading Transient Response" and Engine Data Sheet, LEKX4067, "Transient Response".Power Factor
Power factor (PF) is the ratio of real power to apparent power. The real power is also known as the active power, or kW. The apparent power is also called kVA. Real power (kW) is the mechanical power output of the engine converted to electrical energy, consumed by the load. The apparent power (kVA) is the total power that is produced by the generator. Power factor can be calculated by using the following formula:PF = kW / kVA,kW - kilowatts (real power)kVA - Kilo-Volt-Ampere (apparent power)kVAR - kilo-Volt-Ampere (reactive power)Note: The generator does NOT control power factor. Power factor is determined by the load.In most applications, loads such as electric motors, solid-state controls, and transformers determine the power factor of the system. Induction motors usually have a power factor that is no larger than 0.8. Incandescent lighting is a resistive load of about 1.0 power factor, or unity. Solid-state controls, variable frequency drives (VFD), variable speed drives (VSD), and control systems Uninterruptible Power Supplies (UPS) can operate at any power factor, leading, or lagging. In this case, the power factor can be between 0.4 and 1.0.The power factor of a system may be determined by a measurement or by calculation and is displayed on the control panel.Note: Normally, Caterpillar generators are designed for a power factor between 0.8 lagging and 1.0. Consult your Caterpillar dealer to check the generator rating if the operation at less than 0.8 lagging power factor or operation at a leading power factor is desired.Excitation Systems
Refer to the Operation and Maintenance Manual, "Voltage Regulators" for information on excitation systems.Generator Options
Space Heaters
Space heaters can be fitted as an optional accessory for operation in all climates.