GP50 / GP35L inspection, grease exchange and battery replacement
The GP50 and the GP35L have the same maintenance; only the R-axis grease amounts differ. Inspection intervals are counted in hours with the servo power ON. For high-frequency handling applications, ask YASKAWA for an individual review.
Turn the power off and tag it out before maintenance. If you disconnect the connector between a motor and the multi-port connector, the encoder absolute data (ABSO data) is lost.
Inspection items
| No. | Items | Schedule | What to do |
|---|---|---|---|
| 1 | Alignment mark | Daily | Check that the marks match at the home position and are not damaged (or check for misalignment at the check point) |
| 2 | Working area and manipulator | Daily | Check for seeped oil, cracks and damage; clean off dust and spatter |
| 3 | Baseplate mounting bolts | 1000 h cycle | Check for missing or loose bolts and tighten |
| 4 | Covers, bolts for the connector base | 1000 h cycle | Check for missing or loose bolts and tighten |
| 5 | Connector for manipulator cable | 1000 h cycle | Check by hand for loose connectors |
| 6 | Protective tubing | 1000 h cycle | Clean the spatter; check for holes and tears |
| 7 | Wire harnesses in manipulator (S- to T-axes, power supply board included) | Daily / 12000 h / 24000 h | Daily visual check for damage and dirt; every 12000 h check the harness and wear of the protective spring; replace at 24000 h |
| 8 | Battery pack in manipulator | 24000 h | Replace when the battery alarm occurs or at 24000 h |
| 9 | Motors for all axes | 12000 h cycle | Check for grease leakage |
| 10 | Speed reducers for all axes | 12000 h cycle | Check for malfunction and replace grease |
| 11 | B- and T-axes gear | 12000 h cycle | Check for malfunction and replace grease |
| 12 | Overhaul | 36000 h | Done by the YASKAWA service department |
The manual also states, for each item, whether it may be done by specified personnel at the user, by a licensee, or only by a YASKAWA representative.
Grease used
| Specification | Speed reducers for all axes, B- and T-axes gear |
|---|---|
| -A00 (standard) | Molywhite RE No.00 |
| -D00 | RV grease LB00 |
For the drip-proof and food grade grease specifications, see the variants page.
Grease exchange for the speed reducers and gears
Conditions to keep
- Always remove the plug from the grease exhaust port before injecting. With the plug in place, grease can leak into the motor or push out the oil seal of the speed reducer. A tube on the exhaust port must be 150 mm or shorter with an inside diameter of 6 mm or more.
- Inject with a grease pump (for example an air-operated grease gun) at 7 g/s or less. At 2 shots per second, that means 3.5 g per shot or less. Keep the air supply pressure of the grease pump at approximately 0.3 MPa or less.
- When extruding grease by air, keep the pressure at 0.025 MPa or less (also 0.025 MPa or less for the suction pressure). Grease can shoot out, so lead it into a container with a tube.
- Fill the hose on the grease inlet with grease first, so no air enters the speed reducer.
- After mounting a speed reducer or motor, wait 30 minutes or more for the sealing bond to harden before injecting grease.
Amount of grease (approx.)
| Axis to exchange grease | Amount of grease |
|---|---|
| S-axis | 2750 g |
| L-axis | 1410 g |
| U-axis | 640 g |
| R-axis (GP50) | 3050 g |
| R-axis (GP35L) | 4700 g |
| B-, and T-axes, B-, and T-axis gear | 1310 g |
The GP50 / GP35L maintenance manual gives no separate amount for the first supply only.
Key steps
- Set the recommended posture for grease injection: L-axis 0° for the L-axis; L-, U-, R- and B-axis 0° for the U-, R-, B- and T-axes (if the L-axis posture is not possible, make the U-arm horizontal to the ground). When wall-mounted, the L-axis is at ±90°. The positions of the grease inlet and exhaust port depend on the mounting condition, so check them first.
- Remove the hexagon socket head plugs from the grease inlet and grease exhaust port, install the grease zerk (delivered with the manipulator) on the grease inlet and inject.
- When exchanging grease, stop when old and new grease come out of the exhaust port in about equal amounts, and go to step 5. When replacing the speed reducer, stop when grease can be seen at the exhaust port.
- (Speed reducer replacement only) Operate each axis about 5 times in the teach mode (S-, L-, U- and B-axis ±45°, R- and T-axis ±90°, user-specified speed), then inject again until grease comes out of the exhaust port.
- Discharge the amount below. Weigh the grease in a container while you either extrude it by air from the exhaust port (0.025 MPa or less) or suction it out of the exhaust port. If little comes out, operate the axis about 5 times in the teach mode.
| Axis to exchange grease | Amount of exhausted grease |
|---|---|
| S-axis | 0 (unnecessary) |
| L-axis | 190 ± 25 g (215 ± 30 cc) |
| U-axis | 90 ± 10 g (100 ± 15 cc) |
| R-axis (GP50) | 155 ± 20 g (175 ± 25 cc) |
| R-axis (GP35L) | 235 ± 35 g (270 ± 40 cc) |
| B-, and T-axes, B-, and T-axis gear | 65 ± 10 g (75 ± 10 cc) |
- Perform the running-in operation by playback: the exchanged axis at ±45° (R- and T-axis ±90°), MOVJ VJ=50.00, timer 1.0 s after each operation, for 15 minutes. Grease may come out during the operation, so first remove the grease zerk, install the plug with seal tape TB4501 on the grease inlet, and attach a grease receiving bag to the exhaust port.
- Wipe off the discharged grease and install the exhaust port plug, also with seal tape.
If too little grease is discharged, the inner pressure rises during operation and grease leaks. If too much is discharged, lubrication is insufficient and the speed reducer wears early.
Plug type and tightening torque
| Axis | Plug for the grease inlet | Plug for the grease exhaust port |
|---|---|---|
| S-axis | PT1/4, 12 N·m (1.2 kgf·m) | PT3/8, 23 N·m (2.34 kgf·m) |
| L-axis | PT3/8, 23 N·m (2.34 kgf·m) | PT3/8, 23 N·m (2.34 kgf·m) |
| U-axis | PT1/8, 4.9 N·m (0.5 kgf·m) | PT3/8, 23 N·m (2.34 kgf·m) |
| R-axis | PT1/8, 4.9 N·m (0.5 kgf·m) | PT3/8, 23 N·m (2.34 kgf·m) |
| B-, and T-axes, B-, and T-axis gear | PT1/8, 4.9 N·m (0.5 kgf·m) | PT1/8, 4.9 N·m (0.5 kgf·m) |
Clean and degrease the thread of each plug, then wrap seal tape TB4501 around it. When ceiling-mounted, the grease inlet and exhaust port are swapped.
Stay out of the manipulator's range of motion while it moves.
Replacing the battery packs in the manipulator
There are three battery packs (HW1483880-A): for the S- and L-axes, for the U- and R-axes and for the B- and T-axes, each installed with a multi-port connector. Replace them when the battery alarm appears on the programming pendant, or at 24000 h.
- When the YRC1000 power can be turned on: turn ON the power supply of the YRC1000, turn OFF the servo power, and work with the emergency stop button pressed. Remove the cover, cut the cable tie, swap the old battery pack for the new one and fix it with cable ties. The data is kept because the power is on.
- When the power cannot be turned on: prepare the lead wires for battery replacement (HW1471281-A) and a separate battery pack for backup. First connect them to the "IN" (or "Y") port of the multi-port connector, then replace the old pack. Otherwise the encoder absolute data is lost.
Related articles
- GP50 / GP35L specifications
- GP50 / GP35L drip-proof and food grade grease specifications and zeroing function
- Encoder battery replacement
- Home position calibration
- Alarm 4312 ENCODER BATTERY ERROR
Source: based on YASKAWA manuals HW1484658 (GP50/GP35L instructions rev 6, Japanese), HW2481410 (GP50 instructions -D00 rev 1, Japanese only) and HW1484672 (GP50/GP35L maintenance manual rev 3, Japanese). English terms follow HW1484659 (MOTOMAN-GP50,GP35L INSTRUCTIONS rev 6) and HW1484673 (MOTOMAN-GP50,GP35L MAINTENANCE MANUAL rev 3).