PIN 9G5859 - Caterpillar

3304, 3306, 3406, 3408, 3412 Industrial And Marine Engines Equipped With SR4 GeneratorsReference: "New Time Delay Conversion Groups Available" on Page 7 of the August 23, 1982 Service Magazine.Description of Change: The reference article tells about two conversion groups which are available to install a new type of electronic time delay on the above model engines, in place of the former oil pressure orifice timer. Design changes have now been made to use the new time delay as original factory equipment in new control panels. With the change in control panel design, several other improvements have been made, including: ... A new diode is connected to contact six of the time delay auxiliary relay.... Four circuit breakers are used to keep damage at a minimum after failure of a component. Two 20 Ampere circuit breakers are used for protection of the shutoff solenoids, one in each circuit; a 60 Ampere circuit breaker is used for protection of the optional battery-charging alternator circuit; and a 10 Ampere circuit breaker is used for protection of the logic circuit wiring. This circuit breaker operates by isolation (separation) of the component which has the failure (sensor, relay, or printed circuit board) from the remainder of the control panel.
Adaptable To: Identification of the new control panels can be made by the four circuit breakers on the front, as shown in Illustration 1. Illustration 2 shows the back of the front panel (as seen in the open position), and Illustration 3 shows the logic panel (24 Volt) with the new 3T6392 Diode. Illustration 4 is a schematic wiring diagram of the new control panel, which can be used as a reference for service until Service Manual revisions are complete. As shown in the reference article, earlier units can be changed to use the new electronic time delay by installation of either the 2W6384 (for 3304 and 3306 Engines) or the 2W6386 (for 3406, 3408, and 3412 Engines) Time Delay Conversion Group. A Special Instruction, Form SMHS8082, is sent with each group for installation.
Illustration 1. Front view of control panel.
Illustration 2. Back of front panel as seen in the open position.
Illustration 3. View of logic panel (24 Volt).
Illustration 4. Schematic wiring diagram for new control panel.