LINK Systems OmniLink II Press Automation Control - Manual (Page 58)

August 30, 2002 Manual Version 1.0 4.9
If the loss of motion time value calculated by the formula is not longer than the time that motion
can dip below the Minimum Press Speed, loss of motion faults will result. If these occur, you may
increase the time calculated by the formula but, in no case, should this time be increased more
than 2.5 times the value calculated by the formula.
Section 4.2.1.4 Temporarily Setting Other Items on the Machine Parameter Screen So that the
Press Can be Stroked Without Generating Brake Monitor or Motion Detector Faults
The previous configuration settings could be done without having to stroke the press to a particular
position in the stroke. The next setting in the Machine Parameter configuration menu, Encoder Offset,
will require you to Inch the press slide to either the top or the bottom of the stroke. The OmniLink II
Press and Automation Control provides a Brake Monitor and a Motion Detector as a standard feature. If
the clutch engagement time limits or either the top stop or mid stroke stop limits are set below the actual
clutch engagement time or the actual stopping time of your press, they will generate faults that will have
to be reset. To avoid these faults, temporarily make these settings:
1. Clutch Engagement Time Limit : 200 msecs (milliseconds)
2. Brake Monitor Top Stop Limit : 500 msecs
3. Brake Monitor Mid Stroke Stop Limit : 500 msecs
These settings will prevent faults for most presses. But, if you have a press with clutch engagement time
greater than 200 milliseconds or stop time greater than 500 milliseconds, you may have to increase the
settings listed above to prevent having to reset faults during the next configuration steps that require
stroking of the press. Note! These are temporary settings only! You will need to refine these
settings later in the configuration process as described in section 4.1.1.8.
Section 4.2.1.5 Setting Encoder Offset
Once the Encoder Type is set, use the down arrow key to select Encoder Offset. The Encoder Offset
setting must be performed so that your system indicates the correct crank or eccentric shaft angle.
The Encoder Offset is a setting that compensates for limited (+/-10
o ) mechanical angular misalignment
between the resolver shaft angular position and the crank or eccentric shaft angular position, so that the
resolver and crank do not have to be perfectly mechanically aligned during installation.
Two methods of setting the encoder offset are described in this section, one with the slide positioned at
top dead center (TDC), and one with the slide positioned at bottom dead center (BDC). For simple
eccentric motion mechanical presses (which constitute the vast majority of presses), with slide driven by
crankshaft, eccentric shaft, or eccentric gear, the top of stroke position always occurs with the crank at
the 0
0 (TDC) angular position and bottom of stroke at the180 0 (BDC) position. You may use either
method of encoder offset for simple eccentric motion presses.
For Link Drive presses, bottom of stroke still occurs at the180
0 (BDC) position, but top of stroke will
generally occur at a crank or eccentric angle between 315 0 and 335 0 , depending on the specific design.
You must use the method that positions the slide at BDC for link drive presses.