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SENSOR S HALL EF FECT SENS OR Chapter Issue 2 Oct 06 Technical Reference Manual 31.3 HALL EFFECT SENSOR Descriptio n The board stop ext ended Hall ef fect sen sor is acti vated by a magnet fi tted to the board stop pist …

SENSORS

INTRODUCTION

31.2 Technical Reference Manual Chapter Issue 2 Oct 06

Conventional

Switches

The machine 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 31-2 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 machine uses the following types of analogue sensor:

• Giant Magneto Resistive Sensor

• Strain Gauge Sensors

• Temperature and Humidity Sensor

Sensor Location Machine 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+ (User)

12V

Opto-isolator

1K8

0V (User)

Signal I/P

Conventional

Switch

SENSORS

HALL EFFECT SENSOR

Chapter Issue 2 Oct 06 Technical Reference Manual 31.3

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 31-3 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 31-4 Voltage Diagram

Hall Effect Sensor

Hall Effect

Magnet

V+ (User)

Opto-isolator

1K8

0V (User)

12V

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

On OnOff

Hall Effect

Signal

Present

SENSORS

OPTO SENSORS

31.4 Technical Reference Manual Chapter Issue 2 Oct 06

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 screen, 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 (screen position sensor) and the Rising Table Module

chapter (remote board at stop) of this manual, (Adjustments and Settings

section).

V+ (User)

NPN

Opto-isolator

1K8

0V (User)

Pin 1 12V

Pin 3 0V

Pin 2 Signal

12V

Control

Circuit

View on Arrow A

Sensitivity/Focal Length

Adjustment

Red LED - Target Detected

Background Suppressed Opto

Emitter/Receiver

Digital Input