Oil change cycle and oil quantity
The oil change cycle of the HC version is similar to that of the standard version, but it needs to refer to the maintenance table. The standard model lubricates the balance cylinder bearings every 5000 hours or at the latest 1 year, checks the balance cylinder pressure every 5000 hours, replaces the gear oil every 20000 hours or at the latest 5 years, and replaces the balance cylinder every 10 years. The maintenance cycle of the F variant is shorter, with lubrication and pressure checks every 2500 hours or 1 year, and oil changes every 10000 hours or 5 years.
Oil change amount: A1 about 5.70 L, A2 about 2.10 L, A3 about 1.40 L, A4 about 2.10 L, A5/A6 about 1.90 L. Use Optigear Synt. ALR 150 gear oil. When changing the oil, the gearbox should be at operating temperature, and the discharge amount depends on the discharge time and oil temperature. The refilling amount must be consistent with the emission amount. If the emission amount is less than 70% of the specified oil amount, it needs to be flushed once with discharge oil; If it is less than 50%, rinse twice. Move the axis within the full axis range at a jog speed during flushing. The tightening torque of the magnetic plug is 25 Nm for A1, 20 Nm for A2, 20 Nm for both the upper and lower parts of A3, 40 Nm for both the upper and lower parts of A4, and 20 Nm for A5/A6. When operating, pay attention to hot oil burns and oil chamber pressure, and exhaust before discharging.
When checking the balance cylinder, manually move A2 to -90 ° C, wait for 1 minute, press the emergency stop button, and read the digital sensor pressure: 176 bar ± 5 bar at 20 ° C. The deviation between the analog pressure gauge and the digital sensor should not exceed ± 10 bar. If the pressure is abnormal, please contact KUKA service and do not adjust it without authorization.

Key points for motor replacement
Before replacing the motor, it is necessary to comply with 5 electrical safety regulations: cutting off the power supply, locking to prevent restart, confirming no voltage, grounding and short circuiting, covering or isolating adjacent live parts. Simultaneously press the emergency stop button to prevent the robot from accidentally moving. When the motor is just stopped, the surface temperature is high and protective gloves should be worn; There is a risk of crushing during disassembly and assembly, and protective gloves should also be worn.
A1 motor replacement: Remove XM1 and XP1, unscrew 4 M12x25-8.8 screws, and lift out the motor. Clean the teeth before installing the new motor, apply a small amount of Microlube GL 261, and check the O-ring. Install 4 M12x25-8.8 screws and tighten them diagonally in steps. Connect plug, zero point calibration, T1 test.
A2 motor replacement: First, fix the connecting rod arm with a sling, remove XM2 and XP2, hang A2 motor, unscrew 4 M12x45-8.8 screws, and pull out the motor. Clean the teeth and apply lubricating grease during installation. Install 4 M12x45-8.8 screws and tighten diagonally. Connect the plug, remove the connecting rod arm stopper, calibrate the zero point, and conduct T1 testing.
A3 motor replacement: Secure the robot arm with a sling, remove XM3 and XP3, suspend the A3 motor, unscrew 4 M12x45-8.8 screws, and pull out the motor. Clean the teeth and apply lubricating grease during installation. Install 4 M12x45-8.8 screws and tighten diagonally. Connect the plug, remove the arm stopper, zero point calibration, T1 test.
A4 and A5 motor replacement: Remove the motor cover, unplug XM4/XP4 or XM5/XP5, unscrew 4 M8x40-8.8 screws, and remove the motor. Clean the teeth and apply lubricating grease during installation. Install 4 M8x40-8.8 screws and tighten diagonally. Connect the plug, zero point calibration A4, A5, A6, T1 test.
The replacement of A6 motor is the most complex, requiring the removal of A4 and A5 motors, additional brakes A4/A5, and then the wire harness wrist, followed by the removal of A6 motor. During installation, follow the reverse order and ensure that the motor connector is located diagonally in the lower left corner, and that the compression spring is in good condition. After completion, MAMES values need to be adjusted (KSS 8.3 requires KUKA. KristMamesOffset plugin), zero calibration A4, A5, A6, and T1 testing.
Common troubleshooting ideas
Patient rescue failure: Check if the battery is fully charged, if the storage box cover triggers STOP 1 normally, if the emergency stop button on the handheld device is reset, and if the connecting wires X25/XG25 are locked. If rescue is carried out after the controller is turned off, re mastering is required.
Additional brake alarm: Check if the additional brake connectors XBr2 to XBr5 are locked and if the brake is worn or stuck. After replacing the additional brake, it is necessary to re master the corresponding axis.
Abnormal balance cylinder pressure: Check the pressure gauge, digital sensor, leakage point, and bellows. When the pressure is below the allowable range, contact KUKA service and do not inflate it without authorization.
Communication interruption or RDC failure: Check if the X30/XD30, X31/XF31, X21/XF21 connectors are locked, if the cable bending radius is too small, and if the shielding and grounding are good.