Wintriss SmartPAC PRO Servo, User Manual

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1147100 SmartPAC PRO Servo User Manual
124 Chapter 5
– Program Mode
Green Constant Sensors
When you set a sensor input to “green constant,” the sensor must turn on before the Ready signal
begins and turn off after the Ready signal ends, remaining actuated continuously during the entire
Ready signal, Figure 5-20.
Figure 5-20
. Ready Signal Programming for a “Green Constant” Sensor
Green Special Sensors
CAUTION
GREEN SPECIAL SENSOR MAY NOT PREVENT DAMAGE
Use the green special sensor with caution. An undesirable number of slugs can stack up in an
ejection hole while still satisfying a green special sensor’s requirements. See the example below.
Failure to comply with these instructions could result in property damage.
Green special sensors are designed to monitor slug ejection, signaling when slugs have stacked up
excessively in a slug ejection hole. Slugs are not necessarily ejected on every stroke. Several strokes
may be required before they finally break free and fall out of the bottom of the die. If the slugs jam
and too many stack up in the hole, the die can be damaged.
Slug stacking is virtually impossible to monitor with a standard green sensor. A red or yellow sensor
is equally ineffective because the sensor changes state whenever a slug is ejected.
Instead of actuating once per stroke like a typical green sensor, the green special sensor must actuate
at least once during a preset number of strokes. Rather than setting a Ready signal, you set the
maximum number of strokes that the press can make without the sensor actuating.
For example, if your die clears all the slugs from a particular ejection hole approximately once every
four strokes, you would set a Green Special sensor input for a six-stroke window. If no slugs are
ejected after six strokes, SmartPAC PRO Servo sends a Stop command to the press.
Example: How a Green Special Sensor May Not Detect a Problem
Referring to the case cited above, assume that the press makes five strokes without ejecting a
slug. On the sixth stroke, one slug ejects and actuates the sensor. The green special sensor is