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SENSORS INTRODUCTION 40.2 Technical Reference Manual Chapter Issue 6, May 19 Conventional Switches The printer uses the following type s of conventional switch sensors: • Reed Switch • Safety Switch • Microswitch •P r e …

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SENSORS
INTRODUCTION
Chapter Issue 6, May 19 Technical Reference Manual 40.1
CHAPTER 40 SENSORS
INTRODUCTION This chapter gives details of the various sensors used in the printer. All sensors
used on the printer fall within three categories, these are:
• Solid State Switch Sensors
• Conventional Switch Sensors
• Analogue Sensors
Solid State
Switches
The printer uses the following types of solid state sensor switches:
• Hall Effect Sensors
• Opto Sensors
• Ultrasonic Sensor
• Capacitive Proximity Sensor
In all cases to initiate a logic 1 (on state) at the input, the sensor must connect
the signal input to 0V. This may not, however, translate to a positive condition
after software processing.
Figure 40-1 Typical Solid State Schematic
Testing Solid state sensors can only be tested in circuit as they require a logic supply
voltage and a pull up resistor on the sensor output.
1. Check for the 12V logic supply to the sensor.
2. Activate the sensor according to type and measure the voltage at the output
terminal with respect to 0V. The sensor output signal should change
between approximately 0V and 12V (see individual sensor descriptions for
more details).
Digital Input
+V
12V
Opto-isolator
1K8
0V
Signal I/P
Control
Circuit
Solid State
Sensor
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