FAULT FINDING |
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This fault finding guide goes no further than the replacement of the major assemblies such as power supply,
The
| ⎯ | Main Interface PCB |
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| ⎯ | Processor PCB |
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| ⎯ Low voltage power supply |
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| ⎯ | LCD Display panel |
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| ⎯ Front panel keys assembly |
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| ⎯ | Beacon receiver (optional) |
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Note | The LCD display panel has a replaceable backlight which has | |||
| a finite life span. This light will need replacing within the | |||
| working life of the | |||
| instructions on replacing the lamp. |
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FAULT SYMPTOMS |
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INTRAC doesn’t appear | Check that the main | |||
to power up | switched on. If not check INTRAC fuse, power cable and | |||
| power source |
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Display screen blank/dark | Data is visible on screen but display is very dark. | |||
| Try to adjust display brightness and contrast. Contrast | |||
| adjustment has some effect but brightness has none. | |||
| LCD backlight or its inverter has failed. | |||
Note | To adjust brightness or contrast press menu keys 2 - 4 - 5 | |||
| followed by the Enter key. Menu key 4 will now control | |||
| brightness and menu key 3 will control contrast. | |||
| Display is bright but there is no data visible. Brightness | |||
| control has some effect but contrast does not. | |||
| Check power supply voltages :- |
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| ⎯ | V1 = +5v to com | ) | Voltages should be |
| ⎯ | V2 = +15v to com | ) | |
| within 5% of stated | |||
| ⎯ | V3 = 12v across + & − | ) | |
| values | |||
| ⎯ | V4 = 24v across + & − | ) | |
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If voltages are correct fault is with LCD, ribbon cable to J18 (Interface PCB) or the Interface PCB itself.
Replacing the LCD backlight | This section applies only to units fitted with a display with a |
| fluorescent tube backlight (blue display). Some units may be |
| fitted with a LED backlight display (grey display) which do not |
| require replacement of the backlight. |
| Remove the top cover from the |
| LCD panel is then visible. |
Page 78 | © 2011 Advantech Wireless |
