York 00497VIP manual Display Replacement Kit, Service

Service

to the next HSYNC pulse. All YORK applications operate in the DISPLAY ENABLE mode. The state of the ENABLE (Display Interface Board J1-27) signal from the Microboard places the Display in the desired mode as follows:

•LG SEMICON Display does not have the fixed mode feature.

As described above, in OptiView Control Center applications, the Display scan is left to right, beginning with the top row and continuing sequentially through the rows to the last row. However, in Display applications other than OptiView Control Centers, image reversal is sometimes required. In image reversal applications, the scan is reversed; the scan is right to left, beginning with the last row and proceeding to the top row.

Displays by different manufacturers can require different timing and control signals. The Microboard must know which Display is present in order to provide the correct signals. Therefore, when AC control power is first applied to the OptiView Control Center, as part of the power-up sequence, the Microboard reads the Panel ID wire jumpers P1D0 - P1D3 on the Display Interface Board and determines which Display is present. It can then provide the correct timing and control signals to produce the graphic image, as required by the Display manufacturer. Since the Display Interface Board identifies the Display for the Microboard, there is a different Display Interface Board required for each Display application and each has a unique jumper configuration that identifies the Display. A complete explanation of this process is included in the preceding “Microboard” description and the “Display Interface Board” description that follows.

The DC power source to operate the Display is provided by the Microboard J5. Some Display manufacturers require +5VDC; others require +3.3VDC. The position of Microboard Program Jumper JP2 determines which of these power sources is supplied to the Display. JP2 must be positioned according to the Display manufacturers requirements. Refer to Table 2, “Program Jumpers”.

The Backlight Lamp provides the illumination for the display. Average lamp life is 25000 hours (2.9 years). Some displays use one lamp. Others use two lamps. Lamps are replaceable, but not interchangeable between different displays. Each Display manufacturer specifies the required lamp for their display. Refer to replacement parts list for appropriate replacement lamp. Service replacement lamps are stocked in theYORK Service Parts

Distribution Center. The lamp is illuminated by applying a high voltage AC (500 to 1500VAC) to it. This illumination voltage is created from a low level DC voltage (+12VDC or +5VDC as required by the Display manufacturer) by the Backlight Inverter Board. Lamp brightness is controlled by varying the high voltage AC. The greater the voltage the brighter the illumination. The lamp is controlled by on/off commands and brightness control signals applied to the Backlight Inverter Board from the Microboard. The Microboard Program determines when the lamp is turned on and off and the lamp brightness. Each Display manufacturer specifies the Backlight Inverter Board to be used. Therefore, it will vary according to the Display manufacturer. The ribbon cable that connects the Microboard to the Backlight Inverter Board also varies according to the Display manufacturer’s requirements. Refer to Fig. 44. Microboard Program Jumpers JP3, 4, 5, 7 and 8 determine the voltage levels of the control signals sent to the Backlight Inverter Board and must be configured per the Display manufacturer’s requirements as listed in Table 2. A detailed description of the operation of this board is in the “Backlight Inverter Board” description that follows. Also refer to the preceding “Microboard” description for a detailed description of the Lamp Dimmer circuit.

The actual Display that is installed in the OptiView Control Center of the new chiller is determined by the Display manufacturer contractual agreement in place during the time of OptiView Control Center production. Displays stocked for Service replacement are a result of that same agreement. Therefore, the Display received for service replacement may be by a different manufacturer than the one in the OptiView Control Center. Since each Display manufacturer requires a specific Display Interface Board, Backlight Inverter Board and Inverter Ribbon Cable, replacement Displays are ordered and supplied as a Display Replacement Kit (YORK Part Number 331-02053-000) to assure component compat- ibility. The items supplied in the kit are compatible with the supplied Display. The kit consists of the following items mounted on a Display mounting plate:

Display Replacement Kit 331-02053-000:

1.Liquid Crystal Display with Lamp

2.Appropriate Display Interface Board for item 1

3.Appropriate Backlight Inverter Board for item 1

4.Appropriate ribbon cable (Backlight Inverter Board to Microboard) for item 1

5.Ribbon cable (Display Interface Board to Microboard)

6.All mounting hardware

7.Installation instructions. A label attached to the

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