Position Error between Encoders

When error [4.1050] occurs, the following symptoms may appear:

• Servo on fails. The error is raised as soon as the servo is turned on, sometimes even in recovery mode.
• The robot works for a moment after servo on, then stops with the error, often with a clicking sound.
• Only one axis is affected. The error is raised every time that axis is jogged a few degrees, or when it reaches the same angle.
• From Param 1, you can identify which inverter (joint) the error occurred on.

[4.1050] Robot inverter category

Position Error between Encoders
Param 1: Inverter Number
Param 2: 0xFF18

Each joint has two encoders that measure its position. This error means the two no longer agree, so the robot stops because it cannot tell which position is correct.

• Encoder cable or connection inside the joint — the most common cause, including a connection disturbed during disassembly or repair.
• Collision or impact — contact with a wall, a jig or another robot shifts the joint.
• Wear in the joint — play in the reducer from age or after a collision.
• Settings after an update or part replacement — the joint settings no longer match the hardware.

These parts are inside the robot arm and need service.

• Turn the robot power off completely and restart it. If the error does not come back, continue operating and watch whether it recurs.
• Note the axis from Param 1, and whether the error appears at servo on, at a specific angle, or at random during operation.
• Check whether a collision or a hard stop happened just before the error.
• Note whether the robot was recently disassembled, repaired, updated or had a part replaced.

If the error returns, contact your distributor.

• Robot model and serial number
• Software version of the controller
• The error code with its Param values, all codes shown with it, and the date and time
• Collision history, and any recent repair, update or part replacement
• The controller log exported right after the error

• 5.7069 The difference between the incremental encoder and the absolute encoder values exceeds limit range — see Incremental and Absolute Encoder Difference Exceeds Limit
• 4.1017 Absolute Encoder CRC Error
• 5.7057 Current joint position exceeds user limit in at least one joint
• 4.1049 Incremental Encoder Count Error
• 4.1025 Position Following Error
• 2.4901 FTS exceeds allowable limit (A-Series)