GO ORDNANCE !!! ORDNANCECORPS 1 Troubleshoot the DC Electrical Control System on the EPP III

GO ORDNANCE !!! ORDNANCECORPS 2 ID symbols on the wiring diagram Time Delay Relay Lights Ground Gages Switches normally open and closed Connector plugs

GO ORDNANCE !!! ORDNANCECORPS 3 ID symbols on the wiring diagram Starter Motor Battery Charging Fuel Solenoid Thermo resistor Diode Relay normally open contacts Circuit Breaker Relay normally Close contacts Wire number Regular relay

GO ORDNANCE !!! ORDNANCECORPS 4 When you energizes a relay, you must reverse the contacts. Locating the contacts is not easy. The wiring diagram makes it easy. The sheet that the relay coil is on has the key. Look at the bottom of the sheet for the relay number, under it you will find the contact numbers and grid location. Contacts 2 and 1 are normally open. They are located on sheet 1 of 11 and in grid D1.5. EXAMPLE K D 1.5

GO ORDNANCE !!! ORDNANCECORPS 5 Key Inserted Circuits:  Fuel level gage indicates fuel level  Frequency meter shows “0000”  Low oil pressure light comes on  Battery charging light comes on  K10 Arms  K2 energize

Key Inserted Wire 0 is negative throughout the generator. Close the S1 switch and turn to sheet four.

Start at the ground on the fuel level sensor to energize the fuel gage. Turn to sheet 3 and follow wire 14 all the to sheet one.

Start at wire 14 through the S1 and go down to the positive side of the battery. The fuel gage will show the amount of fuel in the tank. Now turn to sheet nine.

Start at wire 0 and go through the P5, and turn to sheet four.

Start at P5+, and follow wire 14. The Frequency meter will now read Turn to sheet three.

Start at wire 0 to arm K10. K10 is now armed it will energize in 30 seconds, its contacts will reverse but nothing will happen unless the generator goes into a low oil pressure condition. Pick up the circuit at the 1S2, low oil pressure switch to turn on the low oil light. Turn to sheet four and start at wire 94.

Start at wire 94 and go through the N5 to wire 14. Turn to sheet one.

Start at wire 0 and go through the 1G3. Follow wire 7 to sheet two.

Follow wire 7 to sheet three.

The battery charging light is now on. We will now energize the K2, start at wire 7. Follow wire 26 to sheet 2.

Start at wire 26 K2 is now energized all its contacts will reverse. Look on the bottom of the page using the contact chart and reverse all of K2 contacts. Then proceed to the next slide.

GO ORDNANCE !!! ORDNANCECORPS 17 Crank and Start circuits Components:  K28  S2 switch  Batteries  FK  1M1  FK  Fuel solenoid  N1  R10  MPU  Actuator Crank Start

Pre-Heat and FuelCrank Circuit Start by placing the S2 in position 1. The switch will line up to wire 19. The glow plugs will warn up for 90 seconds then the light will come on. Fuel is now being dumped into number 1 and 2 cylinders to aid in starting the generator. Pick up the circuit at the grounds on the heater plugs and solenoid valve and go up to the switch. The light is now on and the operator can start the generator. Now place the S2 in position 2, wires 50a, 17, and 4 should line up. Turn to sheet three.

Start at wire 7 and then go to sheet one.

Start at wire 7 and go through the V15 to energize the K28. K28 is energized its contacts reverse. The first two close and allow the starter motor to be energized. The last set closes to keep the negative at the K28. Pick up the circuit at wire 0 to energize the starter. Turn to sheet two.

Start/Fuel Run Circuit Start at wire 0 and go through pins 12 and 13 to turn on the N1. Turn to sheet one and follow wire 24.

Start at wire 24 and go through the K5 contacts, the V3 to the S2. Turn to sheet two.

The N1 now has 24VDC, it still needs 1.5VAC from the magnetic pickup on pins 10 and 11. With these two inputs the N1 will have an output on pins 1, 2, 4, and 5 to the control devices. Pin 3 is negative. The generator is now running. Turn to sheet one.

GO ORDNANCE !!! ORDNANCECORPS 24 Battery charging circuit Components:  1G3  N6  P7  FK  R11

Battery Charging When you release the S2 K28 will de-energize. Start at the 1G3 and go to the N6. With a input from the 1G3 to the N6. The N6 will have an output to the 1G3 of 27.5VDC to charge the batteries. Wire 7 with had negative potential will now have positive potential. Follow wire 7 to sheet three.

Start at wire 7 and go up to the diodes. The battery charging light goes out. The K2 de-energizes and its contacts reverse back to the normal positions. The low oil lights goes out. Turn to sheet one.

GO ORDNANCE !!! ORDNANCECORPS 27 Run Safety circuit Components:  K2  K5  F3

Run Safety When you release the S2, power is lost to the N1. Power to keep the N1 energized goes through the K5, K2 contacts, and the F3. Turn to sheet five.

GO ORDNANCE !!! ORDNANCECORPS 29 Field Flash circuit Components:  K3  K6  K26  N2  F7  F9  M2

Field Flash Start at wire 0 to arm the K3. Follow wire 41 to sheet four.

Start at wire 41 and go up to wire 14. Turn to sheet five. K3 is armed.

K3 take 30 seconds to energize, then it contacts will reverse. It is now energized. Close the contacts and start at wire 0 to energize the K6. Follow wire 14 to sheet four. Then come back to sheet five. The K6 contacts are holding contacts. Close the contacts. Turn to sheet seven.

Start at wire 0 to arm the K26. Follow wire 43 all the way to the K6 contacts on sheet five. K26 is armed it take seven seconds to energize. Now turn to sheet nine.

Start at wire 0 and go through the N2 up to wire 43 to turn on the N2. Follow wire 43 all the way back to the K6 contacts, and turn back to sheet nine. The N2 will now have an output from pin J to the F1 and F2 and back to pin K. The generator will now start producing voltage. Now turn to sheet ten.

AC VOLTAGE This is the AC voltage that the generator produces after field flash. You will now see the P6 show voltage. Turn to sheet nine.

Start at wires 144 and 145 to the T14 and T15. Now pick up the circuit at wires 78, 79, and 80 into the N2 and N3. Turn to sheet five.

Seven seconds has past and K26 is energized, its contacts reverse. Turn to sheet seven.

GO ORDNANCE !!! ORDNANCECORPS 38 AC circuit interrupter Components:  K13  K14  K26 contacts  S12, 13, 14 and15  S7  S8  K1

K1 Main contactor Circuits Start at wire 0 and go to wire 43 to arm K13. Follow wire 43 all the way to the back to the K6. Follow wire 138 all the way to the K26 contact and up to wire 41.

Here are the interlocks on the 150Kw Generator Set. When the cables are connected to the generator the interlocks S12 thru S15 are pressed in. They must be closed before the K1 will energize.

Here is a look at the interlock on the inside of the control panel. This is where you make the checks.

K13 take 13 seconds to energize. The operator must wait until K13 is energized before pushing the S8. Close the K13 contacts and press the S8. Pick up the circuit at wire 0 to energize the K14. The S12 – 15 must be pressed in before the K1 will energize. They are pressed in when the cables are tight. K14 is energize and it contacts reverse. The first set is a holding contact to keep K14 energized. This set closes to energize the K1. Pick up the circuit at wire 0 to energize the K1. K1 is energized turn to sheet ten to reverse its contacts.

AC OUTPUT Close the K1 contacts now the generator will have an output to the load terminals. Start at the K1 contacts. Follow wires 114, and 115 to sheet nine.

Start at wires 114, and 115.

GO ORDNANCE !!! ORDNANCECORPS 45 Troubleshooting We are now ready to troubleshoot, but before we get started the next slides will explain the use of the technical manual. We are using the Direct Support Troubleshooting Chart in Chapter 5.

Some of these troubleshooting chart are very long, but they can be shorten.

This is the Symptom Index Chart a list of the malfunction that you will use during troubleshooting.

Let’s look at chart Diesel engine cannot be started, Figure 5-4.

BATTERY CHARGING CONTROL and OIL PRESSURE lamps do not light up (sheet 1 of 7) Measure voltage at 2G2/+ and 2G1/-: 24 VDC? Measure voltage at 2G2/+ and FK/0 input-: 24 VDC? Measure voltage at 2G2/+ and FK/0 output-: 24 VDC? Measure voltage at FK2/Input and : 24 VDC? T Measure voltage at 2G2/+ and : 24 VDC? T Continue Page 2 Check Battery set 2G1/2G2 and Cable “1” (PARAGRAPH 4.74) Repair Replace Wiring harness, cable “0” Repair Replace FK (PARAGRAPH 5.16) Repair Replace cable “0” Repair Replace Wiring harness, cable “0” YES NO

Figure 5-4 Diesel engine cannot be started (sheet 3 of 10) Measure voltage at K2/A1, V13 and K2/A2 V13: 23 VDC? Measure voltage at S2/50 and : 24 VDC? Measure voltage at K28/A1 and H2/X6/1: 24 VDC? Continue Page 4 Replace S2 (PARAGRAPH 4.50) Repair or Replace cable “38” Repair or Replace cable “7” Repair or Replace Cable “26” NOYES Replace K2/V13 (PARAGRAPH 5.6) T NO YES Measure voltage at K28/A1 and V15/ 24 VDC?

Figure 5-4 Diesel engine cannot be started (sheet 7 of 10) Measure voltage at S2/15 and : 24 VDC? Measure voltage at V3(Anode) and : 24 VDC? Continue Page 8 Replace S2 (PARAGRAPH 4.50) Repair Replace cable “0” Replace V3 (PARAGRAPH 4.62) T T Repair or Replace cable “14” Measure voltage at S2/17 and : 24 VDC? Repair or Replace cable “4” T Measure voltage at V3(Anode) and N1/12 R10: 24 VDC? Measure voltage at V3(Cathode) and N1/12 R10: 24 VDC? NO YES

This is the place to start. Figure 5-4 Diesel engine cannot be started (sheet 3 of 10) NOMeasure voltage atYES S2/50a and : 24 VDC Replace S2 (PARAGRAPH 5.16 Measure voltage at K28/A1 and H2/X6/1: 24 VDC NO YES

When the engine rotates and the diesel engine still will not start, you will start troubleshooting on sheet 7. Look at the block below for the starting point. Remember this, S2/19 is for the glow plugs, S2/50a is for engine crank and S2/17 is for N1 and the rest of the fuel system. NO Measure voltage at S2/17 and : 24 VDC YES

GO ORDNANCE !!! ORDNANCECORPS 54 When reading the malfunction chart tests there is one very important word to look for and the word is And Any component and pin listed on the left side of the word “AND” is where the POSITIVE Lead of the multimeter goes. Any component and pin listed on the right side of the word “AND” is where NEGATIVE Lead of the multimeter goes.

GO ORDNANCE !!! ORDNANCECORPS 55 In some of the test there can be 2 or more checks to be made. Look below at the examples. Measure voltage at K2/52, 62, K5/52, 62 and N1/12, R10: 24VDC This test is checking two contacts of the K2 and two contacts of the K5. You move the positive lead of the multimeter to the contact pins leaving the negative lead of the multimeter in one place, N1/12. R10’s negative side is mounted on pin 12 of the N1.

GO ORDNANCE !!! ORDNANCECORPS 56 There will be times when the troubleshooting chart will let you pick where to put the negative lead of the multimeter. Look at the example below. Measures voltage at F5(Output) and : 24 VDC When you choose the ground point MAKE SURE THAT THERE IS NO PAINT. MUST BE BARE METAL!

When you have this malfunction there are some checks you can make to shorten the steps. Look at K2 relay, if the plunger is down when you insert the key you can start you troubleshooting on sheet 3 of 10.