GeoBrick Axis Homing

[rhombusvs]

Hi I've got a geobrick with 6 axes used (out of 8) #1..4,#7,#8 and I am having problems getting the motors to home to the PLIMx flag All the limits work when I have 1xx24=$1 so I know the limits are OK. I have used one of the homing routines from the user manual as a template and come up with this CLOSE OPEN PROG 102 CLEAR //Home Z1 down I224=$20001 ; Disable hardware limits I223=5 ; Home speed 5 cts/msec negative direction I226=-15360 ; home offset to get off switch I7022=2 ; Capture High level flag I7023=1 ; Use PLim2 as trigger flag #2HM ; Do actual homing move I324=$1 ; Re-enable hardware limits CLOSE With Imn22=2 the axis starts to move and then stops, as if it instantly sees the limit flag (even though it is nowhere near it) With Imn22=10 (low Flag Level) it moves continuously to the correct limit but does not see the flag. What am I over looking? Graeme

[Jay Lee]

There are three problems in this: 1. It's better to use a PLC rather than a motion program to do this. 2. "#2HM" is an online command, when you compile your motion program, it should give you an error for that line. Please check the manual for the homing command. The command of homing in motion program is "HOME n", where n is motor number 3. If you use motion program to do homing, right after "HOME n" command, you need to have a wait time to wait for the motor to home. Also check Ixx97 to see if you set the flag capture right. [quote='rhombusvs' pid='582' dateline='1280423415'] Hi I've got a geobrick with 6 axes used (out of 8) #1..4,#7,#8 and I am having problems getting the motors to home to the PLIMx flag All the limits work when I have 1xx24=$1 so I know the limits are OK. I have used one of the homing routines from the user manual as a template and come up with this CLOSE OPEN PROG 102 CLEAR //Home Z1 down I224=$20001 ; Disable hardware limits I223=5 ; Home speed 5 cts/msec negative direction I226=-15360 ; home offset to get off switch I7022=2 ; Capture High level flag I7023=1 ; Use PLim2 as trigger flag #2HM ; Do actual homing move I324=$1 ; Re-enable hardware limits CLOSE With Imn22=2 the axis starts to move and then stops, as if it instantly sees the limit flag (even though it is nowhere near it) With Imn22=10 (low Flag Level) it moves continuously to the correct limit but does not see the flag. What am I over looking? Graeme [/quote]

[Omron Forums Support]

In response to Jay's post to clarify some points: 1. Both a PLC and a motion program will work for this task, but typically this kind of application (setting configuration variables and homing a motor) is done in a PLC, since it does not require a coordinate system or any move modes. 2. In a motion program, PMAC actually [b]does[/b] wait until the home is complete before executing subsequent moves. However, in a PLC, one must program a wait loop waiting for the home complete, in-position, and desired velocity zero bits to be set. These can be pointed to using M Variables. 3. Ixx97 must be set to 0 or 1 to use the flag capture for homing.