TRANSMISSION ARRANGEMENT 3P7556 - Caterpillar

Illustration 1 g00567869
ETS Junction Box with oil pressure protection (OP), water temperature protection (WT), and overspeed protection (OS) that does not require a switchgear for use on 3200 through 3400 Engines (1) Terminal strips (TS) (2) Wiring harness (3) Electronic speed switch (ESS) (4) Junction box (5) Identification foil (6) Jumper between terminals (TS-2) and (TS-3) (7) Jumper between terminals (TS-3) and (TS-4) (8) Emergency stop switch (ES) (9) Time delay relay (TD) (10) Jumper between terminals (TS-27) and (TS-28) (11) Jumper between terminals (TS-28) and (TS-29) (12) Jumper between terminals (TS-30) and (TS-31) (13) Slave relay (SR1) (14) Slave relay (SR2) for the air shutoff solenoid (ASOS) (if equipped) (15) Grommet assembly for engine oil pressure switches (16) Start/stop switch (SSS) (17) Circuit breakers (18) Engine oil pressure switch (OPS1) (19) Mounting brackets for grommet assemblies
Illustration 2 g00290530
ETS Junction Box with oil pressure protection (OP), water temperature protection (WT), and overspeed protection (OS) that does not require a switchgear for use on 3500 Engines (1) Terminal strips (TS) (2) Wiring harness (3) Electronic speed switch (ESS) (4) Junction box (5) Identification foil (6) Jumper between terminals (TS-2) and (TS-3) (7) Jumper between terminals (TS-3) and (TS-4) (8) Emergency stop switch (ES) (9) Time delay relay (TD) (10) Jumper between terminals (TS-27) and (TS-28) (11) Jumper between terminals (TS-28) and (TS-29) (12) Jumper between terminals (TS-30) and (TS-31) (13) Slave relay (SR1) (14) Slave relay (SR2) for the air shutoff solenoid (ASOS) (if equipped) (15) Slave relay (SR3) for starting aid switch (if equipped) (16) Diode for electric governor actuator (if equipped) (17) Grommet assembly for engine oil pressure switches (18) Start/stop switch (SSS) (19) Circuit breakers (20) Engine oil pressure switch (OPS1) (21) Mounting brackets for grommet assemblies (22) Engine oil pressure switch (OPS2) (if equipped)Introduction
The ETS Junction Box with oil pressure protection (OP), water temperature protection (WT), and overspeed protection (OS) that does not require a switchgear is a system that has full protection. The system has a junction box arrangement that is designed to monitor four functions:
Engine overspeed
Crank termination
Oil pressure
Coolant temperatureThe junction box includes the following components:
Electronic speed switch (ESS) (2)
Start/stop switch (SSS) (18) and (16)
Slave relay (SR1) (13)
Slave relay (SR2) (if equipped) with an air shutoff solenoid (ASOS) (14)
Oil pressure switch (OPS1) (18) and (20)
Oil pressure switch (OPS2) that is only in 3500 Engines (22)
Emergency stop switch (ES) (8)
Time delay relay (TD) (9) The components that are listed below operate with the junction box. The components are also mounted on the engine.
Fuel shutoff solenoid (FSOS)
Air shutoff solenoid (ASOS)
Water temperature switch (WTS)The following components must remain de-energized in order for the engine to run with the ETS electric protection system.
Slave relay (SR1)
Slave relay (SR2) (if equipped)
Fuel solenoid (FS)
Air shutoff solenoid (ASOS)Electrical Schematics And Wiring Diagrams
This manual contains the point-to-point wiring diagrams for the complete electric protection system and the junction box. Four types of electrical schematics for each electric protection system arrangement are shown in this service manual.
Junction box wiring diagram
IEC (International Electro-Technical Commission) schematic
JIC (Joint Industrial