Siemens SINUMERIK 840Di Function Manual page 95

Braking behavior
The braking behavior of the machine axis upon reaching the hardware limit switch is
configurable via:
MD36600 $MA_BRAKE_MODE_CHOICE = <
Braking behavior:
• 0: Braking with the configured axial acceleration
• 1: Rapid stop (set velocity = 0)
Effectivity
The hardware limit switch monitoring is active after the control has ramped up in all modes.
Effect
Upon reaching the hardware limit switch, the following occurs:
• Alarm: "21614 Channel <
• The machine axis is braked according to the configured braking behavior.
• If the axis/spindle is involved in interpolation with other axes/spindles, these are also
• The traversing keys of the affected machine axis are blocked based on the direction.
2.3.3 Software limit switch
Function
Software limit switches serve to limit the traversing range of a machine axis. Per machine
axis and per traversing direction, two (1st and 2nd) software limit switches are available.
• MD36110 POS_LIMIT_PLUS (1st software limit switch plus)
• MD36110 POS_LIMIT_MINUS (1st software limit switch minus)
• MD36130 POS_LIMIT_PLUS (2nd software limit switch plus)
• MD36120 POS_LIMIT_MINUS (2nd software limit switch minus)
By default, the 1st software limit switch is active. The 2nd software limit switch can be
activated for a specific direction with the PLC user program.
DB31, ... DBX12.2 / 12.3 (2nd software limit switch minus / plus)
Axis Monitoring, Protection Zones (A3)
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
Direction
< >"
braked according to their configured braking behavior.
Braking behavior
Channel number
> Axis <
Detailed Description
2.3 Monitoring of static limits
>
Axis identifier
> Hardware limit switch
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