SHROUD 2576050 - Caterpillar

Resistors (Backup)
Illustration 1 g00552538
Resistors (Backup)Backup resistors limit the amount of current that is supplied to the proportional reducing solenoid valve (PRV) when the backup switch is in the MAN position. Then, the machine is in the backup mode. The proportional reducing solenoids (PRV) are always connected to ground through the controller. When the machine is in the backup mode, the solenoids are connected to 24 DCV through a backup resistor. When the solenoids (PRV) are controlled by the controller the backup resistors are not used. Each resistor is rated at 47 Ohms and 25 Watts on the M318. Each resistor is rated at 59 Ohms and 25 Watts on the M320.Swivel Switch
Illustration 2 g00540944
Swivel Switch (1) Connection to lower structure. (2) Connection to upper structure.The swivel switch passes electrical signals from the upper structure of the excavator to the lower structure. There are seven possible paths for the signal.Note: The swivel connects the control signals to optional equipment. Blades and stabilizer attachments are examples of optional equipment.Diode Blocks
Illustration 3 g00540998
Typical Diode Block And Schematic SymbolThe diode blocks are used to direct the flow of current. Current flows through a diode in one direction only. In the diode block that is shown in illustration 3, positive voltage flows through the diode from terminal "A", "B", or "C" to terminal "D". A positive voltage would not flow from terminal "D" to terminal "A", "B", or "C".