4/5/2024 2:01 PM | |
Joined: 10/11/2006 Last visit: 9/9/2024 Posts: 5902 Rating: (803)
|
Hello, The Hwlimit switch may have been activated manually or the signal level may be fluctuating 5.7.1 Behavior when approaching and retracting a HW limit switch (S7-1500, S7-1500T) Hardware limit switches are limit position switches that limit the maximum permissible traversing range of the axis. Select the mounting positions of the hardware limit switches so that there is adequate braking distance for the axis when needed. The axis should come to a standstill before a mechanical endstop. Approaching the hardware limit switches In the monitoring of range limitation, no distinction is made as to whether the switches are reached or crossed. When a traversable hardware limit switch is approached, technology alarm 531 is output. The axis is disabled and stopped with the configured braking ramp. When a non-traversable hardware limit switch is approached, technology alarm 531 is output and the configured alarm response is executed. Using the hardware limit switches as reversing output cams during active homing When hardware limit switches are used as reversing output cams during homing, monitoring of the hardware limit switches has no effect during active homing. When hardware limit switches are used as reversing output cams, the axis is braked with the deceleration configured in the dynamic defaults. When planning the distance between hardware limit switch and mechanical endstop during active homing, take into account the dynamic default of the deceleration and the approach velocity. Direction reversal at the hardware limit switch (reversing output cam) (Page 155) Retracting the axis with a traversable HW limit switch In case of a traversable HW limit switch, the position of the axis when the hardware limit switch is detected is stored internally on the CPU. The status of the reached hardware limit switch is reset only after the hardware limit switch is left and the axis is once again in the maximum traversing range. To retract the axis after it reaches the hardware limit switch and to reset the status of the hardware limit switch, follow the steps below: 1. To enable movements in the retraction direction, acknowledge the technology alarm with "MC_Reset". A restart is not required. 2. Move the axis in the retraction direction until the hardware limit switch is exited. – Negative HW limit switch: For retracting, move in the direction of higher position values. – Positive HW limit switch: For retracting, move in the direction of lower position values. Afterwards, the axis must be within the maximum traversing range. If you move the axis opposite the retraction direction before the hardware limit switch is exited, the monitoring is triggered again. ............... ........... https://support.industry.siemens.com/cs/ww/en/view/109817884 |
Last edited by: Jen_Moderator at: 04/08/2024 07:34:36Text formatting optimized. With best regards, |
|
4/8/2024 6:33 AM | |
Joined: 10/11/2006 Last visit: 9/9/2024 Posts: 5902 Rating: (803)
|
Hello, Chapter 5.7.1 ............... NOTE Retracting after technology alarm 531 with polarity-reversed HW limit switch or both HW limit switches active To enable retraction, you can temporarily disable the hardware limit switches with Motion Control instruction "MC_WriteParameter (Page 276)" using parameter "PositionLimits_HW.Active" = FALSE. ........... https://support.industry.siemens.com/cs/ww/en/view/109817884 |
With best regards, |
|
This contribution was helpful to1 thankful Users |
Follow us on