Link 2600 - Figure 13: In Position Input Example

Doc #: L-2600-1023 Page 26 Rev. 02
Sensors that are used as inputs to cyclic channels can have an “Input Type” of either “Normally On” or
“Normally Off”. The event is considered to occur when the sensor switches from its normal state. For
example, if a cyclic channel is programmed to be “Normally Off”, the channel event will occur when the
sensor is “On”. If a cyclic channel is programmed to be “Normally On”, the channel event will occur
when the sensor is “Off”. In the majority of applications, the input type for a cyclic channel is
“Normally Off”.
An additional feature for use on cyclic type channels is the “Delay Strokes” parameter which is
programmable by the operator. This parameter provides the flexibility to use the cyclic type to monitor
events in the production process that may not occur every stroke, but must occur within some number of
strokes. An example of such an application is slug detection, where under normal operation slugs are
allowed to build up and fall out maybe two or three at a time after several strokes. In such a scenario a
slug would not be detected by the sensor on every stroke, this would produce a fault were the “Delay
Strokes” feature not used. The operator can enter a number representing the maximum number of
strokes that can be run consecutively without the slug being detected within the timing window. If the
sensor does not become active within the window for a number of strokes exceeding the “Delay
Strokes” number, then a fault will be generated. By contrast, if the sensor does become active within the
window on some stroke before the counter expires, then the counter is reset and the full count is again
allowed. If the operator desires that the sensor be required to become active on every stroke, then a
value of zero should be entered.
3.3.1.3 In Position
“In Position” type channels
are used to monitor whether
material is fully fed into the
die on each cycle of the
press. A sensor should be
used to detect when the
material to be fabricated is
fully fed into the die.
Figure 13 illustrates an
example of the use of a
sensor used as an input to a
channel programmed for In
Position type. In this
example the material is fed
forward contacting a
spring-loaded lever arm. A
sensor monitors the
position of the lever arm.
When the material is in the correct position, the sensor turns on. If the feed is too short or too long, the
sensor will be off.
When programming a channel for “In Position” type, the operator must enter crankshaft angles to mark
the “Window On” and “Window Off” points for a timing window during which the material will move
into place. The “Window On” angle must be set to a point before the material gets into position. The
Material
Sensor
a) Before Feed Progression b) Correct Feed c) Over Feed
Figure 13: “In Position” Input Example