BEARING-INNER 9S5278 - 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 contained in the "Wye Configuration Diagrams" section show lead numbering for the 4, 6, 10, and 12 lead generators. The diagrams contained in the "Delta Configuration Diagrams" section show lead numbering for the 6 and 12 lead generators.Wye Configuration Diagrams
4 Lead
Illustration 1 g00611469
4 Lead Wye Configuration (for 3306B and 3406C generator sets only)
Terminal T0 is the neutral lead.
6 Lead
Illustration 2 g00611486
6 Lead Wye Configuration
Terminals T4, T5, and T6 become neutral connection when the terminals are tied together.
10 Lead
Illustration 3 g00669334
10 Lead Wye Configuration - High Voltage (for 3306B and 3406C generator sets only)
Terminal T0 is the neutral lead.
Illustration 4 g00611596
10 Lead Wye Configuration - Low Voltage (for 3306B and 3406C generator sets only)
Terminal T0 is the neutral lead.
12 Lead
Illustration 5 g00661863
12 Lead Wye Configuration - High Voltage
Terminals T10, T11, and T12 become neutral connection when the terminals are tied together.
Illustration 6 g00611608
12 Lead Wye Configuration - Low Voltage
Terminals T10, T11, and T12 become neutral connection when the terminals are tied together.
Delta Configuration Diagrams
6 Lead
Illustration 7 g00669319
6 Lead Delta Configuration
12 Lead
Illustration 8 g00669312
12 Lead Delta Configuration
Terminals T6 and T9 become the neutral connection when the terminals are tied together and grounded. This configuration reflects the terminal T2 and T10 connection as the high phase.
SR500 Configurations
Illustration 9 g06267380
SR500 12 Lead Wye Configuration High Voltage
Illustration 10 g06267469
SR500 12 Lead Wye Configuration Low Voltage
Illustration 11 g06267491
SR500 12 Lead Delta Configuration
Grounding the Frame
In any generator set installation, the frame of the generator must be positively connected to an earth ground or to the hull of a vessel. This connection is the first one that is made at the installation. This connection is the last one that should be removed. If the generator set is on flexible or resilient pads, the ground connection must be flexible to avoid possible breakage in later operation.Ground connection cable or straps should have at least the current carrying capacity of the largest lead to the connected load. Joints in cables or 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 and bolted joints are electrically and mechanically sound.Neutral Connections
The generators with Wye Configuration usually have the neutral ground when the generator is installed. However, there are some cases when definite measures which can 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 particular generator electrical characteristics, type of fault and trip rating of the circuit breaker. An undervoltage device may be required to provide an