Cummins/Onan DFEJ Generator Set

⚠ The control is set up at the factory for connection to 240 VAC.

1. Remove the two jumpers between terminals TB1-6 and TB1-7 and connect one jumper between TB1-5 and TB1-6 and the other between TB1-7 and TB1-8.
2. Move selector switch S103 on the control PCB to the up position for 120 V.
3. On the control transformer, remove the two jumpers between terminals H2 and H3 and connect one jumper between H1 and H3 and the other between H2 and H4.
4. Attach a tag to the control box indicating the supply voltage.

⚠ Do not use fan blade to bar over the engine; that can damage blades and cause property damage and personal injury.

Tools: Ohmmeter

1. Measure the resistance of the MPU; replace if not between 1,000 ohms and 1,050 ohms.
2. With the MPU removed, bar the engine until a flywheel gear tooth lines up in the center of the mounting hole.
3. Thread the sensor in gently by hand until it just touches the gear tooth.
4. Back it out 1/4 turn and set the locknut.
5. After adjustment, verify output voltage of the MPU is correct.

⚠ Accidental starting can cause severe personal injury or death; disconnect negative (-) battery cable with insulated wrench.

⚠ Set generator set to off mode before disconnecting/connecting harness connectors.

Tools: True RMS meter, Insulated wrench, Jumper leads

1. Verify power to control: Control Alive indicator should be flashing on base board.
2. Clean battery cable terminals and tighten connections using an insulated wrench.
3. Remove F4 and check continuity; if open, replace with same type/amp rating (5 Amps).
4. If F4 OK, remove connector P7 and check B+ at P7-1 to P7-4 and GND at P7-5 to P7-8.
5. If B+/ground missing, isolate to harness and TB BAT terminal on engine block.
6. If B+ and ground OK, base board may be defective; cycle power by reconnecting P7.
7. Confirm calibration part number matches serial plate; re-enter calibration file if needed.
8. With E-Stop not activated, remove P1 and check continuity between P1-1 (ESTOP-NC1) and P1-2 (ESTOP-NC2).
9. With S12 in Manual, remove P1 and check continuity from P1-6 (MAN) to P1-9 (GND).
10. Remove P3 and check continuity from P3-9 (MAN RUN/STOP) to P3-10 (GND); if none when pressing button, replace front membrane panel.

1. If the Warning or Shutdown status indicator is lit, press and hold the Fault Acknowledge button and release after one second or more.
2. The Warning lamp remains on for 2 seconds, then the Shutdown lamp blinks the fault code.
3. A three-digit code is three sets of blinks separated by a two-second pause (hundreds, tens, ones).
4. The sequence occurs three times per code; the fourth Warning flash indicates the next code.
5. Codes are displayed in succession starting with the most recent (up to 32 stored).
6. To return to the most recent fault code, press and release the Fault Acknowledge button (less than one second) and repeat.

Tools: Ohmmeter, Feeler gauge

1. Remove the fuel pump control cover, disconnect the wiring jack, and unscrew the assembly from the top of the day tank.
2. With an ohmmeter, test for electrical continuity (switch closed) between each pair of colored leads while holding the assembly vertical; replace if any switch is open (readings should be zero).
3. Lift each float to 1/8 inch (3 mm) below the C-clip stop above it (use a feeler gauge); test for continuity; replace if any switch does not open (readings should be infinity).
4. Use pipe thread sealant when replacing the assembly.

Tools: Induction ammeter

1. Charge the battery for a minimum of four hours to ensure the acid is sufficiently mixed; extend the charging period if the battery has been in storage.
2. When the generator set is running, check the charge alternator output using an induction ammeter.

⚠ Commissioning is to be undertaken by suitably trained and qualified service personnel only.

1. Check for any damage to the battery case or terminals, and make sure that the battery is clean and dry.
2. Remove the vent plugs and break any seals (if present), taking care not to damage the plates or separators.

⚠ Even momentary incorrect connection can cause damage to the electrical system.

Tools: Insulated wrench

1. Secure the battery; hold-down bolts must be tight but not over-tight.
2. Smear the terminals with petroleum jelly, if necessary.
3. Fit the vents firmly in position and make sure the battery is clean and dry.
4. Verify correct polarity when connecting the battery to the set.
5. Use an insulated wrench to connect the positive generator cable first, followed by the negative cable.

1. The CT has a dot on one side. This dot must face toward the generator (conventional current flowing into the dot).
2. CT21 - U load leads (A phase); CT22 - V load leads (B phase); CT23 - W load leads (C phase).
3. Route the appropriate load wires through each CT.
4. CT secondaries have 3 pins: secondary wire marked 1 to pin 1; wire marked 2/3 to pin 2 for high voltage gensets or pin 3 for low voltage gensets.

1. CT has dot on one side; dot must face toward generator (conventional current into dot). Dot also indicates pin 1.
2. CT21 – U load leads (A phase), CT22 – V load leads (B phase), CT23 – W load leads (C phase).
3. Route appropriate load wires through each CT.
4. CTs have dual secondaries. Wire 1 to pin 1; wire 2/3 to pin 2 for high voltage or pin 3 for low voltage.

⚠ Wear acid-proof protective apron, goggles, rubber gloves and boots.

⚠ Never add undiluted sulfuric acid to a battery.

1. Fill each cell of the battery with dilute sulphuric acid (electrolyte) of the correct specific gravity according to the levels on the battery label.
2. Filling must be completed in one step.
3. Allow the battery to soak for ten to fifteen minutes; restore the electrolyte level if it has fallen.
4. After filling, place the battery on a commissioning charge within one hour before any load is placed on the battery.

⚠ Prevent accidental starting by disconnecting the starting battery cables (negative first).

⚠ Always disconnect a battery charger from its AC source before disconnecting the battery cables.

Tools: Insulated wrench

1. Make sure the generator set is disabled: stop the set, activate the E-stop, disconnect the battery charger and disconnect the negative (-) battery cable.
2. Install the air filter support assembly on the engine using M8 x 20 mm hex head screws.
3. Secure the rear air filter bracket assembly to the engine with four 3/4-10 x 1-1/2 inch screws and lock washers; torque to 420 N·m.
4. Secure the top air filter support and five air filter brackets with M8 x 20 mm hex head screws; torque to 24 N·m.
5. Use four M10 screws, flat washers and hex nuts and two mounting bands to secure each air filter; torque M10 screws to 52 N·m and band screws to 5.5 N·m.
6. Install an air inlet hood on each of the air filters.
7. Make sure the interior of the connections between the air cleaner outlet and the turbocharger inlet end of the elbow are clean.
8. Secure a hose hump on each outside air filter with one large hose clamp.
9. Secure an air tube to each hose hump with one medium hose clamp.
10. Secure an intake elbow to each air tube with one medium hose clamp.
11. Secure a reducer insert to each inside air filter with one large hose clamp.
12. Secure a hose elbow on each reducer insert with one large hose clamp.
13. Secure the intake manifold and air tube to the elbows with two large and two medium hose clamps.
14. Secure a reducer insert and reducer elbow on the intake manifold and air tube with two medium hose clamps.
15. Install the filter fittings and service indicators, reconnect the negative battery cable, connect the battery charger and place the control in the desired mode.