Differences

This shows you the differences between two versions of the page.

--- plc:how_to_add_mandatory_homing_after_emergency_button_and-or_servo_ready_alarm [2019/01/07 13:19] – skirillov
+++ plc:how_to_add_mandatory_homing_after_emergency_button_and-or_servo_ready_alarm [2019/09/05 13:24] (current) – ivan
@@ Line 1: / Line 1: @@
 ===== How to add mandatory Homing after Emergency Button and-or Servo ready alarm =====
-For many CNC applications, it's very important to have precise machine position all the time. The homing procedure should be done to find the correct machine position if any servo driver fault happens or Emergency button pressed.
+For many CNC applications, it's very important to have precise machine position all the time. The homing procedure should be done to find the correct machine position if any servo driver fault happens or if the Emergency button is pressed.
-<del>However, plasma/gas cutting users don't care about homes quite often and mostly use "working" position.</del>
+Mandatory Homing procedure handler can be implemented with **Software PLC**:
+{{:plc:homing-handler-002.png}}
-Mandatory Homing procedure handler can be implemented with **Software PLC**
+**NOTE:** The homing procedure handler is OFF by default as it has the exit(99); line in the beginning of the program which immediately terminates the PLC as soon as it is started. In order to enable the homing procedure handler, add two forward slashes in front of the exit(99); line to comment it out so that the PLC can proceed uninterrupted:
+{{:plc:homing-handler-003-comment.png}}
 There are Homing flags situated in global variables 7391-7399
@@ Line 20: / Line 22: @@
 The flags are set automatically to "1" if
-  - The myCNC software just loaded
+  - The myCNC software has just loaded
-  - Emergency button pressed
+  - Emergency button has been pressed
-  - Corresponding Servo Ready alarm triggered
+  - Corresponding Servo Ready alarm has been triggered
-Software PLC Homing procedure handler monitors the flags and stops running G-code if any of the flags is set.
+Software PLC Homing procedure handler monitors the flags and stops running G-code if any of the flags is set to 1.
 <code C HOMING_HANDLER.plc>