GASKET 6N8190 - Caterpillar

Lead Numbering
The Wye Configurations and the Delta Configurations are the most common generator lead connections. The following three-phase connection diagrams illustrate the proper connection and lead identification.The leads are numbered clockwise from the top and from the outside inward. The diagrams that are contained in the figure and figure show lead numbering for the 12 lead generator.Wye Configuration Diagrams
12 Lead Generator
Illustration 1 g00661863
Illustration 2 g06040032
12 Lead Wye Configuration - High Voltage (380–480V, 50/60Hz)
Illustration 3 g00611608Terminals T10, T11, and T12 become neutral connection when the terminals are tied together.
Illustration 4 g06040036
12 Lead Wye Configuration - Low Voltage (220–480V, 60Hz)
Terminals T4, T5, T6, T10, T11, and T12 become neutral connection when the terminals are tied together.Note: If the generator is reconnected from High Voltage to Low Voltage configuration and the nominal generator set rating is to be maintained, then consideration should be given to increasing the size of load cables/braids between the generator terminals and the breaker, as well as increasing the breaker rating. As an alternative the output power should be derated to remain within the current rating of the existing breaker and cables.In any generator set installation, the frame of the generator is positively connected to an earth ground. This connection is the first that is made at the installation. This connection is the last connection that should be removed. If the generator set is on flexible pads or on resilient pads, the ground connection must be flexible. This configuration will avoid possible breakages in later operation.Ground connection cable or ground connections straps should have at least the current carrying capacity of the largest line lead to the connected load. Joints in cables or in straps must be clean, free of electrical resistance, and protected from possible oxidation.Bolted ground connection joints eventually oxidize. The joints are frequent sources of radio frequency interference (RFI). Silver soldered joints and bolted joints are electrically and mechanically sound.The generators with Wye Configuration usually have the neutral grounded when the generator is installed. However, there are some cases when definite measures should be taken to prevent grounds on the load side. The purpose of the grounding of the neutral is to prevent load side equipment damage.If the neutral wire is grounded and one of the phase leads becomes grounded, the excessive current will open a load circuit breaker. The excessive current will also collapse the generator voltage. The result depends on the following items: particular generator electrical characteristics, type of fault, and trip rating of the circuit breaker. An under voltage device may be required to provide an adequate short circuit protection.There are some instances in which grounding the neutral wire is undesirable. In other applications, having an ungrounded neutral lead is acceptable. Definite measures should be taken in such applications to prevent grounds to the phase leads. An example of such measures is ground fault protective circuits. Ground fault protection requires that the entire group of distribution circuits should be studied. The entire group of distribution circuits should be treated as a system. The owner should