17.5 Backlight Shutoff Detection

The backlight is built into GOT for the liquid crystal display.

When GOT detects backlight shutoff, the POWER LED blinks green/orange alternately.

The brightness of the backlight decreases with the lapse of usage period. When backlight shutoff is detected or the display becomes unclear, replace the backlight. (GT14 requires LED replacement.)

For replacement of the backlight, contact your nearest sales office or FA Center.

(1)Life of backlight

The usable duration of backlight can be extended by setting to "Screen saving backlight off" in the utility of GOT (GOT set up). For details, refer to the following.

11. DISPLAY AND OPERATION SETTINGS (GOT SET UP)

17.5.1Backlight shutoff detection and external alarm

When the GOT detects a backlight shutoff, the system information set with drawing software is turned on.

You can issue a backlight shutoff of the GOT from the PLC to external devices (such as the lamp or buzzer), using system information.

To avoid any screen touch operation by the user who misunderstands it is in screen saving mode, install an external alarm and interlock the loads that would cause danger.

For details of the system information, refer to the following.

GT Designer3 Version1 Screen Design Manual (Fundamentals)

HINT

Example of alarm output to external device (lamp, buzzer, etc.)

The following provides an example of outputting the backlight shutoff detection signal from a FX Series PLC to an external device, using system information.

Condition: The Write Device is "D20" and all data is used (the button is clicked on the setting screen of drawing software) for the system information assignment.

D36 b14: Backlight shutoff detection (System Signal 2-2) Turned on upon a backlight shutoff.

Used as shown below in the sequence program.

RUN monitor

 

M8000

 

MOV D36 K4M20

 

Backlight shutoff detection

Output to external device of PLC

M34

Activated the output upon backlight

Y***

shutoff detection.

 

"*" indicates the output number at which the external device is connected.

POINT

Precautions for the backlight shutoff status

In the backlight shutoff status, the touch key operates.

Early replacement of backlight is recommended.

17

INSPECTION

MAINTENANCE AND

18

APPENDICESTROUBLESHOOTING

17. MAINTENANCE AND INSPECTION

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17.5 Backlight Shutoff Detection