88192277-01-19 - Micron Technical Reference V9 Volume 4.pdf - 第125页
SENSORS HALL EFFECT SENSOR Chapter Issue 6, May 19 Technical Reference Manual 40.3 HALL EFFECT SENSOR Description The board stop extended Hall ef fect sensor is activated by a magnet fitted to the board stop piston. With…
SENSORS
INTRODUCTION
40.2 Technical Reference Manual Chapter Issue 6, May 19
Conventional
Switches
The printer uses the following types of conventional switch sensors:
• Reed Switch
• Safety Switch
• Microswitch
•Pressure Switch
In all cases to initiate a logic 1 (on state) at the input, the sensor must connect
the signal input to 0V.
Figure 40-2 Typical Conventional Switch Schematic
Testing 1. Activate the sensor according to type and measure the voltage at the output
terminal with respect to 0V. The sensor signal output should change
between approximately 0V and 12V.
2. Remove switch from the circuit and measure continuity, when activated.
In all cases check digital inputs under diagnostics at the MMI.
Analogue Sensors The printer uses the following types of analogue sensor:
• Giant Magneto Resistive Sensor
• Strain Gauge Sensors
• Temperature and Humidity Sensor
Sensor Location Printer location for individual sensors are detailed in the respective module
chapter overview sections, ie Camera Y Home Sensor - can be found in the
Camera System Module chapter.
Digital Input
+V
12V
Opto-isolator
1K8
0V
Signal I/P
Conventional
Switch
SENSORS
HALL EFFECT SENSOR
Chapter Issue 6, May 19 Technical Reference Manual 40.3
HALL EFFECT SENSOR
Description The board stop extended Hall effect sensor is activated by a magnet fitted to
the board stop piston. With power ON and the board stop extended, the output
transistor is switched on and the signal voltage is pulled down to 0V. When the
board stop is retracted the magnet is moved out of range and the Hall effect is
cancelled, switching off the output transistor and the signal is 12V via the digital
input circuit.
Figure 40-3 Hall Effect Schematic
Testing/
Adjustment
With Power ON and a voltmeter connected with +ve to signal (black) and -ve to
0V (blue), the following results should be obtained:
Figure 40-4 Voltage Diagram
Hall Effect Sensor
Hall Effect
Magnet
+V
Opto-isolator
1K8
0V
0V
12V
12V
0V
0V
Signal
(Brown)
(Black)
(Blue)
V+
Control
Circuit
Pin 4
Pin 5
Pin 6
Locking Screw
Sensor
Board Stop Piston and Magnet
Sensor
Digital Input
Magnet
Clear
Present
12V
0V
On OnOff
Hall Effect
Signal
Present
SENSORS
OPTO SENSORS
40.4 Technical Reference Manual Chapter Issue 6, May 19
OPTO SENSORS
Background
Suppressed Opto
The background suppressed opto sensor is a diffuse type sensor. The sensor
incorporates a background suppression by triangulation capability, for precisely
adjusting the sensing distance.
The opto emits a pulsed red light which is reflected by a target when it enters
the sensing distance, not only sensing the reflected light but also the distance
of the object to the sensor.
When the beam of light hits the board or stencil, some of the diffused light is
reflected back and the sensor NPN transistor output state is switched ON.
The pulsed beam of light, which is continuously on, is accurately focused and
is able to distinguish between the target and objects outside the scan range.
Setting Up
Procedure
The procedures for setting up the background suppressed optos are fully
detailed in the Camera System Module chapter (camera board at stop), the
Transport Rails Module chapter (board at left and board at right sensors), the
Screen Change chapter (stencil position sensor) and the Rising Table Module
chapter (remote board at stop) of this manual, (Adjustments and Settings
section).
+V
NPN
Opto-isolator
1K8
0V
Pin 1 12V
Pin 3 0V
Pin 2 Signal
12V
0V
Control
Circuit
View on Arrow A
Sensitivity/Focal Length
Adjustment
Red LED - Target Detected
Background Suppressed Opto
Emitter/Receiver
A
Digital Input