LINK Systems OmniLink II Press Automation Control - Manual (Page 120)

August 30, 2002 Manual Version 1.0 6.15
Figure 6.10 also shows some unacceptable conditions for In Position events. There are three
unacceptable conditions shown. The left unacceptable condition shows that the feed was not in place at
the end of the timing window. This is a fault condition. The center unacceptable condition shows that
the material did arrive in place during the timing window, but was not in place at the end of the window.
As shown in Figure 6.9, this condition could occur in overfeed situations. This is a fault condition. The
right unacceptable condition shows that the material was sensed as being in position before the
beginning of the timing window. This is a fault condition.
The sensor being used to verify material position can be Normally Off or Normally On. The sensor will
switch from its normal state when the material is in position. When a Normally Off sensor is being used
to sense material position; the sensor will be Off when the material is not in place, and will be On when
the material is in place. The example illustrated in Figure 6.9 is an example of a Normally Off sensor.
When a Normally On sensor is being used to sense material position; the sensor will be On when the
material is not in place, and will be Off when the material is in place. An example of a Normally On
application is detecting proper material position by looking for a hole in the material. The sensor is On
when there is material over the sensor. The sensor will switch to Off at the proper feed position when
the hole is over the sensor.
270
0
180
90
Feed Checked
New Material Fed
into position
Material Cut
Away by Die
ACCEPTABLE
270
0
180
90 270
0
180
90 270
0
180
90
UNACCEPTABLE
Figure 6.10 Acceptable and Unacceptable Conditions for In Position Input