MOTN-017

Identify the limiting joint axis

Press MENU > ALARM > F5 [HELP] to view detailed alarm information. Note which joint axis (J1-J6) is reported as exceeding its limit. The alarm detail will show which joint and whether it's a positive or negative limit violation.

Write down the joint number and limit direction - this tells you exactly which axis is the problem and helps determine if it's a reach issue or a configuration issue.

Check current joint angles and software limits

Navigate to MENU > SYSTEM > Variables and check $SCR.$SSCO_MAX_J[GP:1,axis] and $SCR.$SSCO_MIN_J[GP:1,axis] for the limiting joint axis. Compare these values to the joint angle in the taught position by going to the program line, pressing F3 [POINT DETAIL], and selecting F3 [JOINT].

Do not modify software limit system variables without understanding the mechanical limits and collision zones - reducing limits may prevent the alarm but could cause crashes.

Re-teach position with better joint configuration

In T1 mode at 25% override, jog the robot to the desired Cartesian position using COORD type [WORLD] or [USER]. Once at the correct location, try using MENU > TOUCHUP > F4 [CONFIG] to cycle through different robot configurations (F-B, U-D, T-N) to find one where all joints are within limits. Re-teach the position with this configuration.

For positions near the workspace edge, use COORD [JOINT] to manually adjust the limiting axis while maintaining the general position. Sometimes moving J1 by 5-10 degrees and compensating with J4/J6 keeps the tool in place but clears the limit.

Verify motion path with Program Adjust

If the alarm occurs mid-motion (not at the end position), use MENU > UTILITIES > Program Adjust > Position Adjust to shift the entire program or section away from the limit. Check the motion type (Joint vs Linear vs Circular) - Joint moves are more likely to trigger limits during interpolation.

For circular moves, MOTN-017 can occur at the midpoint even if start and end positions are valid. Break the circular move into two smaller arcs or switch to CNT (continuous) termination type to smooth the path.

Verify CONF settings at problem position

Navigate to the program line causing the alarm and press F3 [POINT DETAIL]. Check the CONF string (e.g., 'N U T, 0, 0, 0'). The first three letters indicate Flip (F/N), Up/Down (U/D), and Turn (T/N) configuration. Press F2 [POSN] to see if a configuration warning icon appears.

If CONF shows asterisks or is blank, the position was taught in Cartesian mode without locking the configuration. The controller will choose the configuration during execution, which may differ from what was intended.

Compare configurations between adjacent positions

Check CONF settings for the position before and after the limiting position. Configuration flips (F to N or vice versa) between positions cause large joint movements. Go to MENU > SETUP > Frames > Config Display to enable visual configuration indicators on the teach pendant position display.

Unexpected configuration changes during linear moves can cause joint limit errors mid-path, even if start and end positions are valid. This is especially common near singularities.

Lock configuration and re-teach if necessary

At the problem position in T1 mode, position the robot with all joints within limits. Press F3 [POINT DETAIL], then F4 [CONFIG], and verify the CONF string matches the current physical configuration. Press F5 [SAME CONFIG] to lock the current configuration, then ENTER to save.

For positions near the workspace edge, use 'N U T' (No-Flip, Up, No-Turn) as it generally keeps J2 and J3 in mid-range and away from limits. Flip configurations (F) often push J3 to its negative limit.

Enable or check configuration turn monitoring

Check system variable $SCR_GRP[1].$CNFG_CARE (MENU > SYSTEM > Variables). If set to FALSE, the controller ignores CONF during motion. Set to TRUE to enforce configuration control. Also verify $MOTYPE in the program header - MOTYPE JOINT ignores configuration on linear moves.

If configuration control is causing persistent issues in an existing program, check if $SCR_GRP[1].$SING_CARE is set. Changing singularity handling can sometimes resolve configuration-related limit errors near J1-J2 or J4-J5-J6 singularities.

Verify active tool and user frame numbers

Check the program header or position detail for UFRAME[n] and UTOOL[n] numbers. Navigate to MENU > SETUP > Frames and verify the frame numbers match. Press F2 [DETAIL] on each frame to view X, Y, Z, W, P, R values. Compare to documentation or previous known-good values.

Using UTOOL[0] or UFRAME[0] means no offset is applied - the robot uses the J6 flange as TCP and world frame as reference. If your program was taught with a different frame active, all positions will be offset.