Kval 990-F4, Руководство по эксплуатации

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About the Electrical Panels
2-23
KVAL 990-F4 Operation Manual
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The Photo Electronic Detector 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 a
door is sensed.
• Some detectors have an emitter and receiver built in one unit, such
as an in-feed sensor where a door blocks the light and reflects back
to the unit.
• Some detectors have an emitter and receiver built in separate units, such as the
through beam sensor set at a distance from each other. If an assembly is in between
the two sensors the machine will not operate.
One Package
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
amplitude and generates 0VDC to send to the PLC. When the metal object leaves
the sensing 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
The L imit Switch is activated by an assembly moving a switch arm.
• .Depending on the model of limit switch, the
amount of “pre-travel” (amount of movement from
the arms resting position) is either 5 or 20 degrees
before the limit switch actuates (Clicks).
Switch Arm