Inconsistent Path Accuracy - ABB IRC5 Operating Manual

3.11 Inconsistent path accuracy

Description
The path of the robot TCP is not consistent. It varies from time to time, and is
sometimes accompanied by noise emerging from bearings, gearboxes, or other
locations.
Consequences
Production is not possible.
Possible causes
The symptom can be caused by (the causes are listed in order of probability):
Recommended actions
In order to remedy the symptom, the following actions are recommended (the
actions are listed in order of probability):
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Operating manual - Troubleshooting IRC5
3HAC020738-001 Revision: AA
• Robot not calibrated correctly.
• Robot TCP not correctly defined.
• Parallel bar damaged (applies to robots fitted with parallel bars only).
• Mechanical joint between motor and gearbox damaged. This often causes
noise to be emitted from the faulty motor.
• Bearings damaged or worn (especially if the path inconsistency is coupled
with clicking or grinding noises from one or more bearings).
• The wrong robot type may be connected to the controller.
• The brakes may not be releasing correctly.
Action
Make sure the robot tool and work object
are correctly defined.
Check the revolution counters' positions.
If required, recalibrate the robot axes.
Locate the faulty bearing by tracking the
noise.
Locate the faulty motor by tracking the
noise.
Study the path of the robot TCP to estab-
lish which axis, and thus which motor,
may be faulty.
Check the trueness of the parallel bar
(applies to robots fitted with parallel bars
only).
Make sure the correct robot type is con-
nected as specified in the configuration
files.
Make sure the robot brakes work prop-
erly.
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3 Troubleshooting by fault symptoms
3.11 Inconsistent path accuracy
Info/Illustration
How to define these are detailed in Operating
manual - IRC5 with FlexPendant.
Update if required.
How to calibrate the robot is detailed in Op-
erating manual - IRC5 with FlexPendant.
Replace faulty bearing as specified in the
product manual for the robot.
Replace the faulty motor/gearbox as spe-
cified in the product manual for the robot.
Replace the faulty parallel bar as specified
in the product manual for the robot.
Proceed as detailed in section
leasing Robot brakes on page
Problem re-
59.
55