Yaskawa MP940-MW+ - Manual (Page 11)

TECHNICAL NOTE
MOTION PRODUCT AND ENGINEERING GROUP
Yaskawa Electric America - 2121 Norman Drive South – Waukegan IL 60085
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5/22/2003 11 of 34 eng/PubNumber/MCD
3: Automatic
]
Functions typically performed while in an “automatic” mode are included in the automatic
main program. While this program is executing it is waiting for the user to activate an input to
select a subroutine program. As long as no input is selected, and not in manual mode, the
program scans the blocks in order of 3, 4, 5, 8, 11, 14 then back to 3.
Two key features in this program are important to mention. First, if event block (3)
detects if (user variable) [SystemOk] is true. As long as this condition is true the program will
stay running (recall SystemOk is controlled by the supervisor program). Second, if event block
(4) ensure that (Auto Mode) [Local_Input2] has been selected (in other words if the machine is
not in manual mode, it is in automatic mode) & (homing sequence has been completed) [Homed]
= true. This is a critical interlock that guarantees that more than one main program is not
attempting motion at the same time. This can be especially unsettling if one program is running
the servo in camming mode and another program is attempting to jog.
If a user puts the machine in automatic mode, attempts to execute an automatic
subroutine, nothing will happen, as execution is held at block 4.