R&S ZVA24, Руководство по обслуживанию

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R&S ZVA Repairs
1177.5333.02 3.43 E-11
Replacing LCD A70 and the DC/AC Converter
(See Chapter 5, Spare Parts List Items 910, 930 and drawings 1145.1110, 1145.1390)
The LCD and the associated DC/AC converter are accommodated on a mounting plate. The connection
to the front module controller is made with cables which should also be replaced individually. The
replacement procedure is as follows:
Opening the instrument and removing the front unit

Turn off the instrument and disconnect from the mains.

Remove termination and 3.5mm connection cables (only with option ZVAx-B16)

Remove the 4 screws from the front handles (410), left and right, and take off the front handles.

Remove the countersunk screw (390) next to the display and pull off the front cover (300, 303, 306,
310, 313, 316) forwards

Remove the 2 countersunk screws (610) in the top of the front frame and the 2 in the bottom.

ZVA8: Remove the countersunk screws (168) (2 ), (153), (154), (163), (164)

Pull out the front unit together with the keyboard and display (600, 604) forwards.
Risk of damage
The cables to the front module controller are still connected.

Disconnect the cables to the LCD, the DC/AC illumination converter, the key pad (keyboard), the
tachogenerator and, if necessary, the network connection to the front module controller.
Risk of damage
When disconnecting cables, be especially careful with the cable to the keyboard. It is a
foil cable and can only be removed when the locking device on the foil-cable connector
is released.

Place the key-side of the front unit on a clean surface.
Removing the DC/AC converter

Disconnect the cable from the display (910) to the DC/AC converter (930).

Disconnect the converter cable (950) to the DC/AC converter (930)

Remove the DC/AC converter (930) by undoing the 2 screws (940)