# Pos Limit

This chapter explains the current position, maximum permitted position error, soft position error, and minimum/maximum position limits in the Pos Limit window. Before applying changes, verify the motion direction, mechanical limits, and emergency-stop method.

## Before You Begin

Item | What to Check
--- | ---
Device state | Stop motion and disable the drive before changing protection parameters. Make sure the load is supported and the mechanism cannot move unexpectedly when a threshold changes.
Parameter source | Use protection thresholds from project delivery documents, device specifications, or verified field records. Do not copy parameters from an unknown device.
Original-value backup | Click Refresh to read and record the current values before clicking Apply, so you can restore the last verified configuration if a problem occurs.
Applicability | This window alone cannot confirm model, firmware, or hardware applicability. If an item is missing, read-only, or cannot be written, first check the documentation for the current model and the supported firmware range.

High-risk operation: Apply on a safety page writes protection parameters to the controller, and some are persistent. Stop motion, disable the drive, and secure the load before making changes. Do not change protection thresholds while the device is moving or enabled.

## Pos Limit

Item | Description | Recommendations
--- | --- | ---
Position: | Read-only display of the current position. | Before changing position limits, verify the current position, mechanical zero, travel limits, and limit-switch state.
Max Position Error: | In counts. Limits the position following error. | A limit that is too wide may conceal a following problem; one that is too narrow may trigger frequently during acceleration, deceleration, or load changes.
Soft Pos Error： | In counts. Used for software position-error protection; the reference documentation does not provide a universal recommended range. | If the write fails or the parameter is invalid, first confirm support for the current model and firmware. Do not keep increasing the threshold.
From | In counts. Sets the negative-direction position limit; the valid numeric range is -2147483648 to 2147483647. | After the first change, verify the limit direction and boundary at low speed over a short travel.
to | In counts. Sets the positive-direction position limit; the valid numeric range is -2147483648 to 2147483647. | Must not be less than the minimum position limit. After the first change, verify the limit direction and boundary at low speed over a short travel.

Use the Pos Limit window to view the current position and configure position-error and position limits.

High-risk operation: Position limits directly affect the mechanism's travel boundaries. Before applying them, verify the motion direction, encoder direction, mechanical limits, and emergency-stop method.

## High-Risk Operations

Operation | Risk | Recommendation
--- | --- | ---
Adjust the bus-voltage limits | May make overvoltage or undervoltage protection too permissive or too restrictive. | Set according to the drive and power-supply specifications, then monitor the warning state.
Adjust current limits | May affect output capability and overload protection. | Make small adjustments within the device specifications and monitor current and faults.
Adjust torque limits | May affect output capability, holding force, and mechanical safety limits. | Set according to the device specifications and mechanical-safety requirements.
Adjust temperature limits | May change the temperature-protection trip point. | Set according to the device specifications. Do not raise the threshold merely to suppress a warning.
Adjust position limits | May affect travel limits and mechanical safety. | Verify both directions and the limits at low speed over a short travel.
Adjust speed limits or emergency-stop deceleration | May affect stopping distance, impact, and protection triggering. | Verify against the available safety distance and load inertia.
Adjust stall thresholds or force-control limits | May delay stall protection, cause false warnings, or produce abnormal output. | Start with verified parameters and validate under light load before normal operation.

## Troubleshooting

Symptom | Recommended Action
--- | ---
Frequent warnings or stops after applying settings | Restore the last verified parameters. Check whether thresholds are too narrow, the load has changed, or the power supply is abnormal.
Protection does not trigger as expected | Check whether thresholds are too wide and whether the current control mode matches the actual feedback. Confirm that the firmware supports the parameter.
Some items are missing or read-only | Confirm that the current model, hardware version, firmware version, and project delivery documents support this setting.
Read or write fails | Do not apply repeatedly. First verify the connection, device ID, firmware version, project documentation, and current error state.
Position or speed limits do not match motion behavior | Cross-check Motion, Motor Settings, Feedback Settings, Control Mode, and the protection parameters on this page to avoid conflicting settings.