Universal WPNP-400NI-PIDS, Руководство пользователя

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BASIC PRINCIPLES OF OPERATION
ENCODER SENSOR FOR DIGITAL MODELS
The WPNP-400NI-PIDS-D Digital Printer has been modified to work with Universal’s new PIDS-DIGITAL-CE
Programmable Ink Delivery System. The PIDS Control System requires an encoder signal from the printer to
track web velocity and to enable programming based on web distance traveled. To eliminate the need to install a
separate, friction driven encoder on the moving web, a simple low resolution encoder assembly has been installed
on the printer.
The center hub of the print drum has
four 0.250" diameter steel targets
installed which are sensed by the
inductive proximity sensor as the print
drum rotates.
Warning: The inductive proximity sensor is a very fragile device and must be handled carefully to prevent damage.
The sensor extends out from the side of the printer side frame a short distance to expose the internal LED lights
and enable connection of the communication cable. When handling the printer care must be taken not to damage
the exposed end of the sensor.
INSTALLATION OR ADJUSTMENT OF THE INDUCTIVE PROXIMITY SENSOR
The inductive proximity sensor has been properly installed, adjusted and tested at the factory prior to shipment
and no further adjustment should be required. If for any reason the sensor needs to be re-adjusted, please read
the following instructions carefully.
1 - To remove or re-adjust the inductive proximity sensor you must first slightly loosen the nylon tip set screw. Use
a 5/64" hex driver to loosen the set screw which holds the sensor in position. This set screw can be reached via
the access hole in the top of the frame as shown in Figure 34.
An inductive proximity sensor (A) is
mounted in the side frame of the printer
through an electrically isolated plastic
bushing
(B) .
This design provides the PIDS Digital Control with the required 4 pulse per revolution encoder signal when the
printer is operating and also lets the control know when the web has stopped moving.
FIGURE 34
When the sensor is threaded into the
bushing and adjusted to the correct
position, a nylon tipped set screw
(C)
is used to prevent it from vibrating out
of its proper position.
B
A
C