FINAL DRIVE GROUP 6K4665 - Caterpillar

Description
Illustration 1 g01273590
(1) Transformer "T1" (2) Transformer "T2" (3) Transformer "T3"The left panel of the MMS cabinet consists of the following transformers: T1, T2 and T3.The transformers are 480 V or 230 V transformers that feed the Power Distribution PWA (PWD). The transformers convert the utility input voltage to the following DC voltage:
190 VDC
230 VDC
190 VDC and 230 VDCTransformer "T1" (1) is supplied from the Bypass voltage. Also, the T1 supplies 190 VDC and the T1 supplies 230 VDC to the PWD.Transformer "T2" (2) is supplied from the Output voltage. Also, the T2 supplies 190 VDC and the T2 supplies 230 VDC to the PWD.Transformer "T3" (3) is supplied from the Input voltage and the T3 supplies 190 VDC to the PWD.A thermistor is attached to each transformer on the lower side of the transformer. The thermistor is connected to the "H1" connector of the transformer.The thermistor limits the inrush of current on the powerup of the system.Removal Procedure
Refer to Systems Operation, Testing and Adjusting, RENR9988, "Internal Component Preremoval Steps (MMS System Cabinet)" in order to shut down the system and gain access to internal components.
Remove the two screws that attach the thermistor to the terminal block.
Remove each thermistor from the terminal block.Note: One screw is attached to the "H1" terminal connector and one screw is attached to the "COM" or "H2" terminal connector.Installation Procedure
Illustration 2 g01273627
Wire Connections for the Transformer
Place one lead of the thermistor into the "H1" connector. Place one lead into the "COM" or "H2" connector. Refer to Illustration 2.
Tighten the two screws in order to attach the thermistor.
Table 1
Specifications for the Thermistor    
    Size     Ohm    
T1     32 mm     20    
T2     32 mm     20    
T3     32 mm     20    
Table 2
Specifications for the Transformer    
    Input (V)     Output (V)     Wire Gauge (AWG)    
T1     380, 400, 415, 480     190, 230     10    
T2     380, 400, 415, 480     190, 230     10    
T3     380, 400, 415, 480     190     10