Kval 979-2, Руководство по эксплуатации и обслуживанию

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Description of the Six Light Panel
2-11
KVAL 979-2 Operation/Service Manual
About Sensors
On the 979-2, sensors provide input to the PLC as part of the automation of the cutting process. It
is important to keep the sensors cleaned and aligned to keep the process running smoothly. There
are two classifications of sensors on the 979-2------Photo Electronic and Inductive Proximity Sen-
sor.
The Photo Electronic Decor uses light as a trigger.
• Photo Eye Detectors contain both emitter and receiver. If an object is within the
Photo Eye’s sensing field light from the emitter is reflected from the object back to
the receiver. With
no object is in front of the Photo Eye a constant 24VDC is sent to
the PLC. If an object is sensed by the Photo Eye, 0VDC is sent to the PLC.
• As a result, any of the photo detectors output equals 0VDC when the trim is sensed.
The Proximity Sensor detects metallic objects without touching them.
• An inductive proximity sensor consists of a coil and ferrite core arrangement, an
oscillator and detector circuit, and a solid-state output. The ferrite core and oscillator
create a field generating out the front of the sensor. When a metal object enters the
field, a loss in amplitude occurs. The detector circuit recognizes the loss of ampli-
tude and generates 0VDC to send to the PLC. When the metal object leaves the sens-
ing area, the sensor to returns to 24VDC and sends it to the PLC.
• As a result, if a metal object is sensed, the output of the sensor equals 0VDC.
Refer to Figure 2- 8 on page 11 for some examples of Sensors:
FIGURE 2- 8.
Examples of Sensor
Photo Eye Detector
Emitter and Receiver
in one package
Proximity Detector
Senses metallic
objects