844021 Volvo.Penta Screw

Illustration 1 g00567168
ETS Junction Box with oil pressure protection (OP), water temperature protection (WT), and overspeed protection that requires a switchgear for use on 3200 through 3400 Engines (1) Terminal strips (TS) (2) Electronic speed switch (ESS) (3) Wiring harness (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 air shutoff solenoid (ASOS) (if equipped) (15) Grommet assembly for engine oil pressure switches (16) Wiring harness connections for the switchgear (17) Circuit breakers (18) Engine oil pressure switch (OPS1) (19) Mounting brackets for the grommet assemblies
Illustration 2 g00290563
ETS Junction Box with oil pressure protection (OP), water temperature protection (WT), and overspeed protection (OS) that requires a switchgear for use on 3500 Engines (1) Terminal strips (TS) (2) Electronic speed switch (ESS) (3) Wiring harness (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 air shutoff solenoid (ASOS) (if equipped) (15) Slave relay (SR3) for starting aid (if equipped) (16) Diode for the electronic governor actuator (if equipped) (17) Grommet assembly for engine oil pressure switches (18) Wiring harness connections for the switchgear (19) Circuit breakers (20) Engine oil pressure switch (OPS1) (21) Mounting brackets for the 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 requires a switchgear is a system that has full protection. The switchgear must be provided by the customer. After the customer's switchgear is wired into the junction box, the electric protection system becomes functional. 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)
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 Council) schematic
Junction box wiring harness diagramNote: The line number that follows a component code gives the location of the component on the IEC and JIC schematics.Circuit Operation With No Faults
The steps that follow use a start/stop switch with three positions in order to interface with the switchgear that is supplied by the customer. Connect the contacts of the switch to the terminal strip in the junction box.
Connect the contacts for the START position between terminals (TS-21) and (TS-26) of the junction box.
Connect the second set of contacts for the START position. The contacts are between terminals (TS-5) and (TS-14) of the junction box.
Connect the contacts for the RUN position across the terminals (TS-4) and (TS-5) of the junction box.
Connect the contacts for the STOP position across the terminals (TS-4) and (TS-10) of the junction box. Note: In order to prevent the premature engine shutdown, the start/stop switch must be held in the START position until the engine oil pressure is observed on the engine oil pressure gauge.Engine Shutdown
When the engine is stopped, power is always available across the terminals (ESS-5) and (ESS-6) (line 53) of the electronic speed switch (ESS). Power is also available across terminals (TD-3) and (TD-4) (line 12) of the time delay relay (TD). All of the switches are in the normally open position or the normally closed positions at that time.Connections For Temporary Start-up
If an engine with this system must be temporarily started before the final installation, use the following steps in order to wire the engine.
Connect a jumper wire across the terminals (TS-7) and (TS-8).
Connect a jumper wire across the terminals (TS-8) and (TS-10).
Connect the contacts for the START position on a start/stop switch across the terminals (TS-21) and (TS-26).
Connect the contacts for the STOP position on a start/stop switch across the terminals (TS-4) and (TS-10).All fault circuits are now operational. However, the start/stop switch must remain in the START until sufficient oil pressure exists. A sufficient amount of engine oil pressure must exist and the start/stop switch must be in the START position. If these conditions are not met, the engine will stop. In order to prevent premature engine shutdown, the start/stop switch must remain in the START position until the engine oil pressure is sufficient enough to open the engine oil pressure switch (OPS1). This condition should occur when oil pressure is observed on the oil pressure gauge.Engine Start-up
The start/stop switch that is installed by the customer should have three positions:
START
RUN
STOPWhen the start/stop switch is moved to the START position, the following events should occur in the electric circuit.
The start/stop switch closes the circuit to the starter motor.
The starter motor magnetic switch (SMMS) (line 9) closes a contact (line 3) which energizes the pinion solenoid (PS) (line 3).
The PS closes a contact (line 2) which energizes the starter motor (SM).When the toggle of the start/stop switch is held in the START position, power is always