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Logical OR:
DRVSTAT + O3TRIG
Logical AND:
DRVSTAT * O3TRIG
All others in list
5.6 H
R
OMING
Homing is simply a term used to refer to calibrating the S200 PN to determine the machine
position after power is applied. The idea becomes obvious in an application that drives a ball
screw or other limited-motion applications. Power can be shut down at anytime so the motor
position is uncertain at power up. A method to 'calibrate' the S200 to an absolute position on the
lead screw is required. This is called Homing.
As stated earlier, the S200 PN always requires homing regardless of the Operational Mode
selected. Any motion command without prior homing of the drive after the last power cycle will
cause a warning and not perform motion. There are times when an application, in and of itself,
would not require homing. To accomplish homing in these cases the S200 PN can be configured
(Under the Profile Setup \ Homing Tab) to 'Auto-home upon Enabling the Drive' with 'Set current
position as Home'.
When homing is a machine requirement the S200 PN offers a few common methods:
1. The present motor position can be assigned as the home position.
2. The S200 can be commanded to move to a home limit switch and stop. The position at
which the home limit switch was activated is the home, or reference position.
3. The S200 can be commanded to move to a home limit switch. The position at which the
home limit switch was activated is the home, or reference position. The motor moves
back to the home position.
The user can adjust ramp, speed, and direction for the homing process.
For systems implementing methods 2 or 3 the mechanical activation of the home limit switch
must be designed such that the home limit switch is active at any possible position that the motor
could be at that is considered beyond the home position. If the S200 is commanded, under these
methods, to move home The S200 PN will first look to see if the home limit switch is active. If the
home limit switch is active the motor will go in the opposite direction that it was programmed to
seek home at until the limit switch becomes inactive. At that point the S200 PN will act as stated
in 2 and 3, above. Failure to design a home limit switch system that is maintained when the
machine is past home will not invoke the reversal process and possibly cause a machine crash.
The Home move (execute homing) is always the first motion task – Motion Task 0. This is not
something that the user can change. Execute the homing task can be set as 'Automatic upon
enabling the drive" or not. If the user chooses to not Auto-Home then the Motion Task 0 must be
executed. A digital Input must be assigned as 'Start Move BCD'. When BCD code 0 is applied
and the Start Move BCD is activated the homing process will begin. If the user has no other need
for BCD Select inputs then no inputs need to be assigned for that function as the code will default
to 0 and allow the single Start Move BCD to execute the homing process. Being a Start Move
BCD the input is level-sensitive so the input must be maintained during the process. If the input is
removed the homing process will be stopped.
18
Output comes on of the logical OR of the drive status word,
DRVSTAT, and the OR Mask, O3TIRG evaluates to TRUE. O3
TRIG is the masking word that can be entered in the window below
this choice.
Output comes on of the logical AND of the drive status word,
DRVSTAT, and the AND Mask, O3TIRG evaluates to TRUE. O3
TRIG is the masking word that can be entered in the window below
this choice.
For factory use only
OUTINES
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