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CATERPILLAR®

FORM NO. SENR3201

Generator Set, Industrial & Marine En.gines Electric Protection System Energize To Shutoff (ETS)

ETS JUNCTION BOXES SYSTEMS OPERATIONS

INDEX Component Description Circuit Breaker '" Electronic Speed Switch.......................................................... Magnetic Pickup Oil Pressure Switch Slave Relay Start Aid Switch Solenoids Time Delay Relay Water Temperature Contact Switch

3 5 3 4 4 4 4 5 5 4

Component Locations on Engine

6,7

ETS Junction Box (OP, WT) Circuit Operation: No Faults Electrical Circuits and Wiring Diagrams Fault Circuit Operation Introduction Protection System Battery Drain

14 14 14 15 14 16

ETS Junction Box (OP, WT, OS) Circuit Operation: No Faults Electrical Schematics and Wiring Diagrams Fault Circuit Operation Introduction '" '"

8 8 8 10 8

ETS Junction Box Without Switchgear (OP, WT, OS) Circuit Operation Electrical Schematics and Wiring Diagrams Introduction

12 12 12 12

Wiring Diagrams Full Protection With Switchgear Wiring Diagram Wiring Harness Full Protection Without Switchgear Wiring Diagram Wiring Harness Partial Protection With Switchgear Wiring Diagram Wiring Harness

17

'"

19' 18 '"

21 20 23 22

INTRODUCTION The Energize To Shutoff (ETS) electric protection system is available in three different junction (J) box arrangements. Two ofthe J box arrangements offer full engine system protection (OP, WT, OS), and one arrangement offers only partial engine system protection (OP, WT). AIso, two of the J box arrangements are completely independent aspurchased, while one ofthe arrangements needs outside switchgear to make it functional.

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The ETS type protection system requirement is that the time 'delay relay must arm the system before it becomes effective. Once the system is armed, a problem with any of the engine systems that are monitored will cause the fuel shutoff solenoid to be acti vated. This will ímmediately stop fuel to the cylinders and cause engine shutdown. The full protection system arrangement monitors the engine from starting through 118% of rated speed.

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'UN tsUXES

SYSTEMS OPERATIONS

COMPONENT DESCRIPTION ELECTRONICSPEED SWITCH (ESS)

4W2218 ELECTRONICSPEEOSWITCH(ESS) 1. Verify button. 2. Reset button. 3. "LEO" overspeed light. 4. Seal screw plug (overspeed). 5. Seal screw plug (crank terminate). 6. Seal screw plug (oil step).

The Electronic Speed Switch (ESS)is designed with controls built into a single unit to monitor several functions at the same time. Two different ESSswitches are used, but the only difference is mounting hale location. The functions that the ESS monitors are:

held in the closed position. This will maintain OPSS in closed position until 2 seconds after the engine has completely stopped. This action will prevent the shutoff from resetting below oil step speed.

Engine Overspeed (OS)

Engine Step Oil Pressure

This is an adjustable engine speed setting (normally 118%of rated speed) that prevents engine from running at a speed that could cause damage to the engine. This condition will cause a switch to clase that shuts off both the inlet air and the fuel to the engine.

This is an adjustable engine speed setting that gives protection to the engine from a failure caused by too little oil pressure for a specified speed range. To maintain desired protection through the complete speed range of operation, two different oil pressure switches are used one with a high pressure rating (OPS2), and one with a 10wpressure rating (OPS 1).

Crank Te'rmination (CT) This is an adjustable engine speed setting that signals the starter motor that the engine is firing and cranking must be terminated. When the speed setting is reached, a switch will open to stop current flowto the starter motor circuito The starter motor pinion gear will now disengage from the engine flvwheel ring gear. Oil Step Latch This feature of the ESS is not adjustable. After terminal ESS··l7 has been energized by loss of engine oil pressure, the oil step switch (OPSS) contacts are now

Once the step oil pressure speed setting is made, an engine that runs abo"e this speed setting must maintain an oil pressure that is more than the higher oil pressure switch (OPS2) rating, if oil step latch is used. An engine that runs below this speed setting must maintain an oil pressure that is more than the lower oil pressure switch (OPS 1) rating. If either condition is not correct, a switch will clase to actívate an alarm or cause the fueI to be stopped to the engine.

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ETS JUNCTION BOXES SYSTEMS OPERATIONS

MAGNETIC PICKUP (MPU) WATER TEMPERATURE CONTACTOR SWITCH (WTS)

2

A17561X2

6 MAGNETIC PICKUP

1. Clearance dirnenslon. 2. Magnetic pickup. 3. Wires. 4. Locknut. 5. Gear tooth. 6. Housing.

The magnetic pickup is a single pole, permanent magnet generator made of wire coils around a permanent magnet pole piece. As the teeth of the flywheel ri ng gear go through the magnetic lines of force around the pickup, an AC voltage is made. A positive voltage is made when each tooth goes by the pole piece. Each time the space between the teeth goes by the pole piece, a riegati ve voltage is made. Engine speed is then determined by the frequency of these signals. OIL PRESSURE SWITCH (OPS)

A

WATER TEMPERATURE CONTACTOR SWITCH

This contactor switch is mounted into the cooIant system and is wired to the protection circuit. It has an eIement "that feels the temperature of the cooIant (it must be in contact with the coolant). When the engine cooIant temperature becomes too high, the switch closes to acti vate an alarm or cause the fueI to be shut off to the engine. SLAVE RELAY (SR) This is a standard type relay that, when energized, has contacts that open across one circuit and close across another circuito The circuits are wired so that power to the soIenoids or the 2301 Governor is controlled by the slave relays.

A

'----1

O ~

START AID SWITCH (SAS)

1-S0CKET ~ 3- PIN ~2-PIN VIEW A-A

The optional start aid switch (SAS) is located on the front of the junction box door. It is a spring return switch which has to be held in the ON position. When the SAS is moved to the ON position, the start aid solenoid valve (SASV) energizes to meter a specific amount of ether into a holding chamber. When the SAS is released, the SASV releases the ether to the engine. The start aid circuit can be de-activated either of two ways: l. Electronic speed switch (ESS) crank terrnination (CT) opens its contact at a preset engine speed (stops current to this circuit).

899624X1

OIL PRESSURESWITCH

The oil pressure switch uses a spring loaded piston to acti vate a micro switch for a specific pressure rating, This type of switch has better accuracy over the operating temperature range and uses a much higher electrical contact rating to improve reliabiIity. 4

2: Temperature

of engine becomes high enough to open the start aid temperature switch (SATS). NOTICE

The engine must be cranking befo re using the starting aid switch. Otherwise, damage to the engine- is possible.

t: I::s

JUNCTlON BOXES SYSTEMS OPERATIONS

CIRCUIT BREAKER The circuit breaker is a switch that opens the battery circuit if the current in the electrical system goes higher than the rating of the circuit breaker. A heat activated metal disc with a contact point completes the electric circuit through the circuit breaker. Ifthe current in the electrical system gets too high, it causes the metal disc to get hot. This heat causes a distortion of the metal disc which opens the contacts and breaks the circuit. A circuit breaker that is open can be reset after it cools. Push the reset button to close the contacts and reset the circuit breaker.

This solenoid is located on top of the engine in the air inlet system. When the ASOS is activated, it mechanically shuts the inlet air off to the engine. The ASOS can only be activated by the overspeed switch (OS) or the emergency stop switch (ES).

Fuel Shutoff Solenoid (FSOS) This solenoid is located on the fuel injection pump of the engine. activated, it moves the fuel rack through the governor) to the Fuel

governor or on the When the FSOS is (either directly or Off position.

NOTICE Find and correct the problem that causes the circuit breaker to open. This will help prevent damage to the circuit components from too much current,

TIME DELAY RELAY (TO)

5 CIRCUIT BREAKER SCHEMATIC 1. Reset button. 2. Disc in open position. 4. Disc. 5. Battery circuit terminals.

3. Contacts.

SOLENOIDS Air Shutoff Solenoid {ASOS)

ON/OFF TIME DELAy RELAy

This relay is a special ON/OFF switch with two controls. When energized, one control will make the relay activate immediately and the other control will activate after a delay of 9 seconds (with continuous signal available). The time delay relay is used to arrn the protection system and is energized by the crank terminate circuit, the oil pressure circuit, or both circuits at the same time. AIR SHUTOFFSOLENOID (Typical IIIustration)

The time delay relay has a 70 second OFF delay after signal is removed from both of input terminals TD-l or TD-2.

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ETS JUNCTION BOXES SYSTEMS OPERATIONS

COMPONENT LOCATIONS .ON ENGINE

WATERTEMPERATURECONTACTORSWITCH (3500 Engine Shown) 1. Regulator housing. 2. Contactor switch.

MAGNETICPICKUPLOCATION (3406 Engine Shown) 1. Magnetic pickup.

JUNCTIONBOX OPENEO AIR SHUTOFFSOLENOIO (3500 Engine Shown) 1. Air shutoff housing. 2. Air shutoff solenoid. 3. Aftercooler housing.

FUEL SHUTOFFSOLENOIO (3406 Engine Shown) 1. Fuel shutoff solenoid. 2. Governor.

1. Junction box terminal strips (TS). 2. Electronic: speed switch (ESS). 3. System identification foil. 4. EmE~rgency stop switch (ES) 5. Time delay relay (TO). 6. Slave relays (SR1and SR2). 7. Oil pressure switch and alarm connectorso 8. Circuit breakers (CB5, CB6, CB7).

JUNCTION BOX ANO ENCLOSUREGROUP CLOSEO (3406 Generator Set Engine Shown) 1. Junction box. 2. Emergencystop switch (ES). 3" Circuit breakers. 4. Electrical wiring conduit. 5. Enclosur'egroup (tor high amperage wiring).

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DVAI:.:;

SYSTEMS OPERA TIONS

REAR OF JUNCTION BOX (Mounted on 3406 Engine) 1. Oil pressure switches (OPS1 and OPS2). 2. Oil manifold plugs. 3. Oil pressure switch connectors.

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ETS JUNCTION BOXES SYSTEMS OPERATIONS

ETS JUNCTION BOX (OP, WT, OS)

VIEW B-B

11 12

lA O

I

[f6 VIEW A-A

~A 8

13

14

B99617Xl

ETS JUNCTION BOX - OIL PRESSURE,WATER TEMPERATURE,OVERSPEEO (Shown With Ooor Open) 1. Terminal strips (TS). 2. Wiring harness. 3. Electronic speed switch (ESS). 4. Junction box. 5. Emergency stop switch (E5). 6.I.dentification foil. 7. Base. 8. Slave relays (SR1 & 5R2). 9. Jumpers. 10.0iodes. 11. Start-stop switch (5S5). 12. Time delay relay (TO). 13. Grommets. 14. Circuit breakers (CB).

INTRODUCTION This ETS junction box circuit (full independent system) is a complete system. It is designed to monitor engine overspeed, oil pressure, coolant temperature and starter motor overspeed.

The noínt-to-ooínt wiring diagrams for both the complete engine protective system and the junction box are located in the Wiring Diagrams Section ofthis module. CIRCUIT OPERATION: NO FAULTS

The junction box components inelude an electronic speed switch (ESS), a time del ay relay (TD), a fuel shutoff solenoid (FSOS), an air shutoff solenoid (ASOS), two slave relays (SR 1 and SR2), an oil pressure switch (OPS) or switches (OPS 1 and OPS2), and a water temperature switch (WTS). The ETS system requires that relays SR 1 and SR2 and solenoids FSOS and ASOS must remain de-energized in order for the engine to runo ELECTRICAL SCHEMATICS ANO WIRING DIAGRAMS Make reference to the Electrical Schematic Form No. SENR3203 in the separate Electrical Schematic Section of this Service Manual. This schematic ineludes both the lEC (International Electro- Technical Commission) and the JIC (Joint Industrial Council) syrnbols.

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Engine Stopped .With the engine stopped, power is always available across terminals 3 and 4 (line 12) of time delay relay (TD) and across terminal s 5 and 6 (line 53) ofelectronic speed switch (ESS). At this time all switches are in their normally open or normally elosed positions.

Engine Start-up NOTE: On the front ofthe junction box door there is a start-stop toggle switch that is spring loaded. It wilI automatically return to the center (RUN) position when released from the START position. When the Start-Stop Switch (SSS) is moved to the START position (up), the circuit to the starter motor is elosed across terminals SSS-2 and SSS-l (line 9). The starter motor magnetic switch (SMMS) (line 9) now energizes to elose its contact (line 3) to energize the

r:: I » "'UNl; IION BOXES SYSTEMS OPERATIONS

pinion solenoid (PS) (line 3). Solenoid PS then closes its contact (line 2) to energize the starter motor (SM). When the engine starts to run and the crank termination speed setting is reached, electronic speed switch (ESS) crank terminate switch (CT) opens its contacts across terminals ESS-l1 and ESS-12 (line 9) and closes its contacts across terminals ESS-l O and ESS-ll (line 13). When ESS(CT) contacts open across terminals ESS11 and ESS-12, current flow is stopped to the starter motor circuit and the starter motor (SM) will now stop. At the same time, ESS(CT) contacts close across terminals ESS-l1 and ESS-l O to energize Control 2 (terminal TD-2) ofthe time delay relay (TD) (line 13). After 9 seconds, TD then closes contacts across terminals TD6 and TD-·7 (line 36) to arm the shutoff circuit to slave relay (SR 1) (line 36). Control 1 (terminal TD-l) ofthe time delay will also be energized as soon as engine oil pressure increases enough to make oil pressure switch (OPS 1) (line 15) contacts open across terminals OPS1-l and OPSI-3, and close across terminals OPS 1-1 and OPS 1-2. Energizing TD-l will immediately (no delay) close contacts across terminals TD-6 and TD-7 (line 36) to arm the shutoff circuit to SR!. NOTE: If engine oil pressure (after the 9 second time limit) is still too low to open oil pressure switch (OPS 1) contacts across terminals OPS1-1 and OPSI-3 (line 15), slave relay (SR 1) (line 36) will be energized and engine shutdown will occur. See FAULT CIRCUIT OPERA TION for the complete circuit description with these conditions. Engine Running At Rated Speed With no engine problems and engine running at rated speed, or at sorne speed aboye the optional oil step speed setting, the oil pressure step switch ESS(OPSS) at line 17 is now closed across terminals ESS14 and ESS-13. At the same time, oil pressure switch (OPS2) (line 17) is now open across contacts OPS2-1 and OPS2-3, so there is still nocurrent flow to energize slave relay (SR 1) at line 36. The engine will continue to run with these conditions. OPS2 (line 17) will not open across contactsOPS2-1 and OPS2-3 until oil pressure increases to the OPS2 switch rating for a particular engine. After opening, it will not close again until oil pressure has dropped approximately 35 kPa (5 psi) less than the opening pressure. The oil pressure step switch ESS(OPSS) at line 17 is operated only by engine speed, not by oil pressure.

When oil pressure is the same as or aboye the step oil pressure speed setting (this setting is adjustable), ESS(OPSS) is energized. However, the ESS(OPSS) switch has a built-in 9 second delay before it can close across terminals ESS-14 and ESS-13. This makes sure that engine oil pressure has time to increase enough to open OPS2, or system could constantly activate engine shutdown.

Engine Running At Any Speed Below Oil Step Speed Setting Ifthe engine continues to run at a speed below the oil step speed setting, oil pressure step switch ESS(OPSS) at line 17 remains open and will not complete the circuit to shutdown (even though OPS2 switch at line 17 is closed across contacts OPS2-1 and OPS2-3). Since engine oil pressure has increased enough to open OPSl switch (line 15) across contacts OPS1-1 and OPS 1-3, the engine can safely run at this speed and the oil pressure circuit will not cause shutdown. If the engine is accelerating through the oil step speed setting, the circuit could stiU look the same as described aboye. When engine speed is the same as (or goes above) the oil step speed setting, engine oil pressure must increase enough (above the OPS2 switch rating for a particular engine) to open OPS2 (line 17) within the 9 second time delay of oil pressure step switch ESS(OPSS). The OPSS switch (line 17) will close across contacts ESS-14 and ESS-13 after 9 seconds. At this time, if OPS2 is still closed across contacts OPS2-1 and OPS2-3, engine shutdown will occur. If OPS2 has opened before OPSS has closed, the engine will continue to runo Engine Normal Stop The operator stops the engine by pressing the startstop switch (SSS) from the RUN position (horizontal) to the STOP position (down). When moved to STOP position, SSS closes across contacts SSS-5 and SSS-6 (line 24) to alIow current to flow through time delay relay (TD) contacts TD-6 and TD-7 (line 36) to energize slave relay (SR 1). Relay SR 1 (line 36) will now close across its contacts SR 1-1 and SR 1-3 (line 43) to energize the fuel shutoff solenoid (FSOS) (line 43). The FSOS will now stop the fuel to the engine. After complete engine shutdown is accomplished, the electronic speed switch ESS(CT) closes across terminals ESS-l1 and ESS-12 (line 9) to allow for restart. The engine can now be immediately restarted. -

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ETS JUNCTION BOXES SYSTEMS OPERATIONS

Emergency

Stop Switch (ES)

The emergency stop switch (ES) is a red, mushroom .shaped pushbutton that is located on the front of the junction box door. This pushbutton will shut the engine down and wiU also prevent the engine from being restarted, because it locks in the OFF (in) position. When pushed in, ES creates an open circuit across contacts ES-lA and ES-2A (line 9). At the same time, it closes across contacts ES-3A and ES-4A (line 33) to energize both slave relays (SR2) (line 33) and (SR 1) (line 36). Relay SR2 now closes its normally open contact (line 47) to energize the air shutoff solenoid (ASOS). This effecti vely shuts the inlet air off to the engine. ASOS remains energized until ESS(CT) contacts ESS10 and ESS-l1 (line 13) open again after the engine stop s (air shutoff lever has to be manually reset). Relay SR 1 (line 36) is also energized through ES-3A and ES-3B. Current can now flow through diode (D2) (Iine 35), and the now energized SRl closes its normally open contact (line 43) to energize the fuel shutoff solenoid (FSOS). This stops the fuel to the engine.

A WARNING To prevent personal injury due to accidental starting of the engine, disconnect the batteries during maintenance or repair work. Before starting the engine again, do the steps that follow: l. Correct any faults that may have been the cause of

the emergency shutdown. 2. Manually reset the air shutoff lever (at the top of the air inlet housing). 3. Make sure the ES has been reset (pushbutton is out) on the engine junction box. To reset, turn the pushbutton in the direction shown on the button face. 4. Start the engine again with the Start-Stop Switch (SSS). FAULT CIRCUIT OPERATION Low Oil Pressure (OPS1) When engine is started and begins to run, crank terminate switch ESS(CT) opens across terminals ESS11and ESS-12 (line 9) and closes across terminals ESS11 and ESS-l O (line 13). This immediately arms the system when current is sent to Control 2 (terminal TD2) of the time delay relay (line 13).

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If oil pressure switch (OPS 1) (line 15) has not yet opened, the engine oil pressure has 9 seconds (from the time that TD-2 is armed) to increase to the oil pressure rating necessary to open OPS 1. IfOPS 1 does not open, TD contacts will close across terminals TD-6 and TD7 (line 36) and slave relay (SR 1) at line 36 will be energized (current can now flow through contacts OPS1-1.and OPSI-3 to terminal ESS-17, through diode (D4) at line 17, through jumper between TS-9 and TS-I0 (line 21), and on through contacts TD-6 and TD-7). SRl relay contacts':}Villnow open across terrninals SR 1-1 and SR 1-2 (line 45), and will close across terminals SR1-1 and SRI-3 (line 43). The fuel shutoff solenoid (FSOS) (line 43) is now energized, and will shut the fuel off to the engine. Ifthe engine had been running (with no faults) at a speed less than the oil step setting, and then lost engine oil pressure, the protection system would cause engine shutdown in the same way as aboye. OPSl would close across contacts OPS 1-1 and OPS 1-3 (line 15) when oil pressure decreased to the minimum switch pressure r a t in g , and engine shutdown would o ccur immediately. ' When oil step latch at terminal ESS-17 was energized in both ofthe aboye examples, ESS(CT) contacts 11 and 12 remain open until 2 seconds after speed can no longer be detected. Any attempt to start the engine (until 2 seconds after flywheel rotation has stopped) will be cancelled. This prevents mechanical damage between the starter motor pinion and the flywheel ring gear. Low Engine Oil Pressure (OPS2) (Optional) This condition will only exist if the optional oil pressure switch (OPS2) is used and there is a fault in the high pressure side ofthe oil pressure circuito When engine oil pressure drops below the higher pressure rating of OPS2, the switch will close across contacts OPS2-1 and OPS2-3 (line 17). Since the engine has been running at a speed aboye the step oil pressure setting, the ESS(OPSS) switch at line 17 is already closed. This now makes the circuit complete for current flow to oil step latch at terminal ESS-l 7. The presence of voltage on ESS-l 7 causes the oil step contacts OPSS 13 and 14 to be held closed 2 seconds after engine speed can no longer be detected. Current then flows through diode (D4) (line 17), through jumper across terminals TS-9 and TS-I0 (line 20), through time delay contacts TD-6 and TD-7 (line 36), and on to energize slave relay (SRl) at line 3. When SR 1 is energized, the normally closed switch now opens across contacts SRl-l and SRl-2 (line 45) and closes across contacts SR1-l and SRI-3 (line 43). The circuit is now completed to energize fuel shutoff solenoid (FSOS) at line 43, and the fuel is stopped to the engine.

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,",VI'fl.. IIUN

tSUXES SYSTEMS OPERATIONS

Engine Overspeed

(OS)

When engine speed increases aboye the overspeed setting (118% of rated engine speed) of the electronic speed switch (ESS), the overspeed switch ESS(OS) will close across terminals ESS-8 and ESS-7 (line 29). This completes the circuit from the battery through crank terminate ESS(CT) switch across terminals ESS~11 and ESS-l O (line 13), through ESS(OS) switch to both slave relays [SR2 (line 33) and thru diode (D2' at line 35 to SR 1 (line 36)]. Both SR 1 and SR2 are now energized at the same time. SR2 will close across contacts SR2-1 and SR2-3 (line 47) to activate air shutoff solenoid (ASOS). ASOS (line 47) will now shut the inlet air offto the engine. At the same time, SR 1 will open across contacts SR 1-1 and SR 1-2 (line 45) and close across contacts SR 1-1 and SR 1-3 (line 43). The fuel shutoff solenoid (FSOS) at line 43 is now activated, and will now shut the fuel off to the engine. NOTICE To avoid engine damage, repair or correct the problem that caused engine shutdown before restarting. A reset button on the ESS must be pushed to open the overspeed switch ESS(OS), and the air shutoff lever (at top of air inlet housing) must be manually reset to the open position before the engine can be restarted. Coolant Overheating The current flow for the circuit discussed here is for an engine that is running at any speed with coolant temperature hot enough to close water temperature contactor switch (WTS). When WTS (line 18) closes, the circuit is completed across terminals TS-2 and TS7 (line 18), through diode (D3) at line 19, through

jumper between TS-9 and TS-10 (line 21), through time delay contacts TD-6 and TD-7 (line 36) to sIave relay (SR 1) at line 36. When SR 1 is energized, the switch wil! close across contacts SR1-1 and SRl-3 (line 43). Now the fuel shutoff solenoid (FSOS) at line 43 is energized to shut the fuel offto the engine. The starter motor circuit can now be engaged, but engine cannot be restarted (no fuel available) until coolant temperature drops below WTS switch rating, when the switch can open again. 2301 Electric Governor Control System When the 2301 Electric Governor Control (EGC) is used, all components ofthe protection system are activated in the same way as discussed with the nonelectrie governors. The only difference in the main circuit is that the fuel shutoff solenoid (FSOS) at line 43 is not used. With this circuit, current normally flows from,TS-28 and T~-31 (lines 43 and 44) through prereguíator (PR) at line 48 or fuse (F4) into the EGC. When the engine flywheel is in rotation, current also flows through electrie governor actuator (EGA) at line 52. When a fault in the system causes current to energize slave relay (SR 1), the switch opens across contacts SR 1-1 and SR 1-2 (line 45) and closes across contacts SR 1-1 and SR 1-3 (line 43). When the circuit is opened across contacts SR]-1 and SR 1-2, current can no longer flow to the EGC. This also stop s current to the EGA, and the mechanical spring load in the EGA system wil! now move the fuel controllinkage to shut the fuel off to the engine. NOTE: Except for the aboye differences, al! fault circuits for the protection system are the same for the 2301 Electric Governor as for the nonelectric governors.

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ETS JUNCTION BOXES SYSTEMS OPE:RATIONS

ETS JUNCTION BOX WITHOUT SWITCHGEAR (OP, WT, OS) 5

7

899618Xl

ETS JUNCTIONBOX WITHOUTSWITCHGEAR(OP, WT, OS) (Shown With Ooor Open) 1. Terminal strips (TS). 2. Wiring harness. 3. Electronic speed switch (ESS). 4. Junction box. 5. Emergency stop switch (ES). 6. Identification breakers (CB). foil. 7. Base. 8. Slave relays (SR1 & SR2). 9. Jumpers. 10. Time delay relay (TO). 11. Grommets. 12..Circuit

INTRODUCTION This ETS junction box circuit (full system without switchgear) is not an independent system. It is designed for the customer who already has his own switchgear. After the customer switchgear is wired into . thisjunction box, it becomes functional and will monitor engine overspeed, oil pressure, coolant temperature and starter motor overspeed. The junction box contains an electronic speed switch (ESS), a time delay relay (TD), a fuel shutoff solenoid (FSOS), an air shutoff solenoid (ASOS), two slave relays (SR 1) and (SR2), oil pressure switch(s) (OPS) and a water temperature switch (WTS). With the ETS system, both slave relays and both solenoids must remain de-energized in order for the engine to runo ELECTRICAL SCHEMATIC ANO WIRING DIAGRAMS Make reference to Electrical Schematic Form No. SENR3204 in the separate Electrical Schematic Section of this Service Manual. This schematic ineludes both the lEC (lnternational Electro- Technical Cornmission) and the JIC (Joint Industrial Council) symbols.

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The point-to-point wmng diagrams for both the complete engine protective system and the junction box can be found in the Wiring Diagrams Section of this module. CIRCUIT OPERATION The circuit operation ofthis system will function the same as the Full Independent System except for the operation of the start-stop switch (SSS). To interface with customer supplied switchgear, use the suggestions (for a three position type start-stop switch) that folIow: 1. Connect switch so that START position contacts are across J box terminal strip terrninals TS-21 and TS-26. 2. Connect switch so that one side of RUN position contacts go to J box terminal strip terminals TS-8 and TS-7. Connect other side of RUN position contacts to TS-IO. 3.. Connect switch so that STOP position contacts are across J box terminal strip terminals TS-4 and TS10. NOTE: To avoid premature engine shutdown, switch must be held in the STAR T position until oil pressure is seen on the oil pressure gauge.

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aUJU::S SYSTEMS OPERATIONS

Connections

For Temporary

Start-up

If an engine with this system needs to be started temporarily before installation in plant, use the wiring suggestions that follow: l. Connect ajumper wire across J box terminal strip terminals TS-7 and TS-8, and across terminals TS-8 and TS-lO. 2. Connect a START switch across J box terminal strip terminals TS-21 and TS-22. 3. Connect a STOP switch across J box terminal strip terminals TS-4 and TS-l O. AHfault circuits are now operational as they would be if the engine was in its final installation. The only difference is that the engine must have enough oil pressure to open OPS 1at the time the enginejust starts to runo If not, this circuit will cause immediate shutdown of the engine.

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ETS JUNCTION BOXES SYSTEMS OPERATIONS

ETS JUNCTION BOX (OP, WT) 6

VIEW B-B

.,A ,

I ·,----'~-__.____il .J A

7

11

9

8

VI EW A-A

B99619X1

ETS JUNCTIONBOX - OIL PRESSURE,WATERTEMPERATURE (Shown With Door Open) 1. Terminal strips (TS). 2. Wiring harness. 3. Junction box. 4. Emergency stop switch (ES). 5. Identification foil. 6. Base. 7. Slave relay (SR1). 8. Jumpers. 9. Start-stop switch (SSS). 10. Diode. 11. Grommets. 12. Circuit breakers (CB).

INTRODUCTION This ETS junction box circuit (partial system) is an independent system that is designed to monitor only engine oil pressure and coolant temperature. This system does not require the electronic speed switch (ESS) or one of the slave relays (SR2) [since engine overspeed is not monitored, no air shutoff is necessary] . . ELECTRICAL SCHEMATICS ANO WIRING OIAGRAMS Make reference to Electrical Schematic Form No. SENR3205 in the separate Electrical Schematic Section of this Service Manual. This schematic includes both the lEC (International Electro- Technical Commission) and the JIC (Joint Industrial Council) symbols. The point-to-point wiring diagrams for both the complete engine protective system and the junction box can be found in the Wiring Diagrams Section of this module. . CIRCUIT OPERATION: NO FAULTS

Engine Stopped With engine stopped, power is always available across terminals 3 and 4 (Iine 11) of time delay relay 14

(TD). At this time all switches are in their normally open or normally closed positions.

Engine Start-up NOTE: There is a start-stop toggle switch on the front of the junction box door that is spring loaded. It will automaticaHy return to the center (RUN) position when released from the STAR T position. When the Start-Stop Switch (SSS) is moved to the START (up) position, it closes the circuit to the starter motor across contacts SSS-2 and SSS-1 (line 7). The starter motor magnetic switch (SMMS) (Iine 7) now energizes to close its contact (line 2) to energize the pinion solenoid (PS) (Iine 2). Solenoid PS closes its contact (Iine 1) to energize the starter motor (SM). NOTE: With SSS held in START position, power is always available to the starter motor. When engine begins to run, release SSS back to the RUN position. This now opens the starter motor circuit to stop power to the starter motor. As engine begins to run, oil pressure will open oil pressure switch (OPS 1) across contacts OPS 1-1 and OPS 1-3 (line 14) and close across contacts OPS 1-1 and OPSI-2. This will send current to Control 1 (terminal TD-l) of time delay relay (TD) at line 12. This will immediately close the TD switch (line 32) across con-

r:. I::,JUNl,;TION BOXES SYSTEMS OPERATIONS

tacts TD-6 and TD- 7. The protection system is now armed, and if either oil pressure gets too low or coolant temperature gets too high, engine shutdown will occur automatically. Engine Normal Stop The operator stops the engine by pressing the startstop switch (SSS) from the RUN (center) position to the STOP (down) position. When moved to the STOP position, SSS (line 24) closes across contacts SSS-5 and SSS-6. The current can now flow across time delay contacts TD-6 and TD7 (line 32) to energize sIave relay (SR!). With SRl energized, a switch will close across SRl-l and SRl-3 (line 34) to energize fuel shutoff solenoid (FSOS) and cause engine shutdown. AIso when SSS is moved to the STOP position, the circuit is broken to Control 1 of time delay (line 12). When power is removed from TD-1, a built-in timer makes the switch remain closed for 70 seconds across contacts TD-6 and TD- 7. This makes sure that engine is completely stopped before the switch opens to deenergize SR-1 and FSOS.

NOTICE To avoid possible damage to the starter motor pinion or engine flywheel ring gear, do not attempt to restart engine until engine rotation is completely stopped. The circuit ofthis system is wired so that engine can be restarted again immediately. Emergency

Stop Switch (ES)

The emergency stop switch (ES) is a red, mushroom shaped pushbutton that is located on the front of the junction box door. This pushbutton will cause engine shutdown and will also prevent the engine from being restarted (because pushbutton latches in this position when pushed in.) When pushed in, ES creates an open circuit across contacts ES~1 and ES-2 (line 7). This stops current flow to the starter motor circuit and aIso to Control 1 (line 12) of the time del ay (TD). At the same time, the circuit is closed across contacts ES-3 and ES-4 (line 28) and current can flowacross closed switch of time delay (line 32) to energize slave relay (SR 1). When SR 1 is energized, the switch closes across contacts SR 1-1 and SR 1-3 (line 34) to energize fuel shutoff solenoid (FSOS). This will now cause engine shutdown.

When circuit is opened to Control 1 of the time delay, the TD is still programmed to maintain a closed switch across contacts TD-6 and TD-7 (line 32) for a time period of 70 seconds. The switch will then open across contacts TD-6 and TD- 7 to de-energize SR 1, and the current will now be stopped lo FSOS. Before restarting the engine, do the steps that follow: 1. Correct any faults that may have been the cause for the emergency shutdown. 2. Make sure the ES on the front of the junction box has been reset (pushbutton out). To reset, turn the pushbutton in the direction shown on the button face. 3. Start the engine again with the start-stop switch (SSS). FAULT CIRCUIT OPERATION Oil Pressure Fault (OPS1) As engine begins to run, oil pressure will open oil pressure switch (OPS 1) across contacts OPS 1-1 and OPS 1-3 (line 14) and close across contacts OPS 1-1 and OPSI-2. Current is now sent to Control 1 oftime delay (TD) at line 12. This will immediately close time delay switch (line 32) across contacts TD-6 and TD- 7. The protection system is now armed. If oil pressure is lost after system is armed, the oil pressure switch (OPS 1) will close across contacts OPS1-1 and OPSI-3 (line 14). The current now has a path to terminal TS-8, through diode (D 1) (line 23), and through TD switch (line 32) to energize slave relay (SR 1). Relay SR 1 will now close its normally open contacts (line 34) to energize the fuel shutoff solenoid (FSOS). Fuel is then stopped to the engine to cause shutdown.

NOTICE To avoid possible engine damage, the engine oil pressure fault must be corrected before restarting. If immediate restart is attempted, the starter motor can be engaged and the engine can be cranked. However, the engine cannot be started beca use the fuel remains shut off for 70 seconds after fault circuit was first initiated. After 70 seconds, the time delay switch will open across contacts TD-6 and TD-7 (line 32) to again disarm the system and allow restart.

15

ETS JUNCTION BOXES SYSTEMS OPERATIONS

A WARNING To prevent personal injury due to accidental starting of the engine, disconnect the batteries before doing any maintenance or repair work.

When the circuit is opened across contacts SR1-1 and SR 1-2, current can no longer flow to the EGC. This also stops current to the EGA, and the mechanical .spring load in the EGA system will now move the fuel controllinkage to shut the fuel off to the engine.

Water Temperature Fault (WTS)

NOTE: Except for the aboye differences, all fault circuits ofthe protection system are the same for the 2301 Electric Governor as for the nonelectric governors.

When engine coolant temperature becomes too high, the normally open water temperature switch (WTS) (line 16) closes. This completes the circuit to terminal strip points TS-7, TS-8, through diode (D 1) (line 23), and on through the now closed time delay switch (line 32) to energize slave relay (SR1). Relay SR 1then closes its normally open contacts (line 34) to energize fuel shutoff solenoid (FSOS). Fuel is now stopped to the engine to cause shutdown. After the 70 second time delay, the engine can again be restarted, but will immediatley be shut down again because WTS will still be closed. Wait until engine has cooled down and the cause of the fault has been corrected before trying to restart engine.

A WARNING To prevent personal injury due to accidental starting of the engine, disconnect the batteries before doing any maintenance or repair work. 2301 Electric Governor Control System When the 2301 Electric Governor Control (EGC) is used, all components ofthe protection system are activated in the same way as discussed with the nonelectrie governors. The only difference in the main circuit is that the fuel shutoff solenoid (FSOS) at line 34 is not used. With this circuit, current normally flows from TS-28 and TS-31 (lines 34 and 35) through preregulator (PR) at line 37 or fuse (F4) (line 39) to the EGC. When engine flywheel is in rotation, current also flows through electric governor actuator (EGA) atIíne 40. When a fault in the system causes current to energize slave relay (SR1), the switch opens across contacts SR 1-1 and SR 1-2 (line 36) and closes across contacts SR1-l and SRI-3 (line 34).

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PROTECTIONSYSTEM BATTERY DRAIN There are three components used in the electric protection system that continue to draw small amounts of current from the battery when the engine is not running. These components are the time delay (TD), electronic speed switch (ESS)and the charging alternator. For a system that uses only one ofthese components,

an engine can remain shut down for months without discharging the battery enough to prevent starting. Systems that use two of the aboye components may remain idIe for a month or more without excessive battery drain, but a system that uses all three components can discharge the battery in about three weeks. Cold weather decreases battery efficiency and will reduce these time periods even more. . In most applications, the engine is started weeklyor a battery charger is used to keep the battery at full charge, so few problems have been noted. For those applications where the engine is not used for extended periods (such as rental fleets), the suggestions that follow can be used to prevent battery discharge. If the engine will not be operated for several weeks (without a battery charger), disconnect the battery cable from the negative (-) side of the battery. If it is expected that this condition will happen frequently, the 7N718 Battery Disconnect Switch can be installed for convenience. This switch should be installed between the negative terminal of the battery and the negative terminal of the starter motor. A suitable bracket should be fabricated to mount the switch close to either the battery or the starter motor .(the switch can be mounted inside the power distribution box on generator set engines). In all applications, the 7N718 Battery Disconnect Switch should be mounted within 30° of vertical.

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WIRING DIAGRAMS

INTRODUCTION

The section that follows contains point-to-point junction box wiring diagrams and also junction box wiring harness diagrams. AHETS systems are included and identified individually. These 'diagrams can be helpful for the user who is not familiar with the electrical schematic-type format, or who is interested in the component positíon layout for replacement purposes. Refer to Form No. SENR3211, Symbols and Wiring Codes, for an explanation of the number coding on both ends of each wire in the wiring harness.

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