PUMP GP-FUEL 5431908 - Caterpillar

Load Division-(Speed Droop)
Once two units have been paralleled their share of the load is determined by the governor control setting. If two units of the same capacity and the same governor characteristics have the same governor control settings they will share the load equally.To transfer the load from one engine to the other follow this procedure:The total load must not exceed the capacity of the engine.1. Increase the governor speed control of one unit to increase the load.2. Reduce the governor speed control of the other unit to decrease the load on that unit.3. Raise or lower the governor speed control of both units to change system frequency.Circulating Currents
When two units are paralleled there will be circulating currents. These currents are not doing useful work, but are flowing between the generators. By determining the total generator amperage and subtracting the amperage going to the load, the amount of circulating current can be determined.Circulating currents are caused by voltage differences between the two units.With cold generator sets, circulating current may be as high as 25% of rated amperes, without being considered harmful. Circulating current is part of the total generator current and this total must not exceed the amperage rating.As the generators warm, the circulating currents will decrease. The ammeter readings should decrease slightly, but the voltage meter readings should remain constant.Parallel Operation of Governors
This section is a general description of the function of the engine governor in relation to load division between parallel electric sets. For detailed information on governor controls and adjustments, see the Operation Guide and Service Manual for the engine.It is very important that two basic facts be understood concerning load division between generator sets operating in parallel. First, the power supplied to the generator and thus to the load is a function of the engine. The engine governor settings and the positions of the governor controls determine the amount of power delivered by the engine and the KW load carried by the generator. If the governor control setting is advanced, the engine and generator will assume more KW load. Likewise, decreasing the governor control setting will result in a reduction of load on the unit. Any other units on the line will, conversely, either reduce or gain load at the same time, assuming no change in total load or no change in the governor settings of the other units has taken place. Second, the division of power is not determined by generator excitation or terminal voltage. The Power Factor at which a generator will operate when paralleled with other generators is determined by its excitation. For more discussion on this subject, refer to the section on Parallel Operation of generators.Governors furnished with Caterpillar Powered Electric Sets can be either of two types, governors with fixed speed droop or governors with adjustable