GE DigitalFlow DF868, Руководство по обслуживанию

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DigitalFlow™ Multipurpose Ultrasonic Liquid Flowmeter Service Manual 31
Chapter 4. Parts Replacement
4.5 Installing an Option Card (cont.)
3. There are six 32-pin option card sockets (
J41–J46
) on the rear of the printed circuit board. To install an option card,
insert its 32-pin connector into any available option card socket and gently press the card into place. Make sure that
the pins in the connector are straight and properly aligned with the socket and that the connector is positioned on
the right side of the option card.
CAUTION! Do not force the option card into the socket. If the card does not enter the socket easily, check
for and straighten any bent pins in the connector and try again.
4. Repeat step 3 to install any additional option cards.
5. Place the metal bracket over the option cards, making sure that all option cards are aligned with the plastic card
guides in the bracket. Secure the metal bracket to the printed circuit board with the snap rivets provided. See the
installed assembly in Figure 8 on page 35.
Complete the option card installation by proceeding to Installing the Printed Circuit Board on page 32.
4.6 Replacing the LCD Display
The Model DF868’s measurements are displayed on a a two-pane LCD graphic display panel. The LCD display
normally provides years of dependable service, but it is easily field-replaceable when necessary. To replace the LCD
display, see Figure 8 on page 35 for the component locations, and complete the following steps:
1. Remove the printed circuit board, as described in a previous section of this chapter.
2. Using a 3/16 in. nutdriver, remove the four nut/washer sets that secure the display shroud to the inside of the
console cover. Lift the display shroud off its mounting studs.
3. Using a 1/4” nutdriver, remove the four standoffs that secure the LCD display assembly to the console cover. Lift
the LCD display assembly off its mounting studs.
4. Place the new LCD display assembly over the mounting studs on the console cover and fasten it in place with the
four standoffs. Make sure that the LCD display assembly is oriented as shown in Figure 9 on page 36.
CAUTION! Do not overtighten the standoffs or the display assembly may be damaged.
5. Position the LCD display cables between the two right side mounting studs, and install the display shroud over the
mounting studs. The top and bottom edges of the shroud are bent at a 90 ° angle to the main surface, and these edges
must face inwards toward the display assembly.
Note:
One edge of the display shroud is covered with a piece of black electrical tape. This side of the shroud should
be on the right, to protect the cables against abrasion.
6. Fasten the display shroud to the console cover with the four sets of nuts/washers.
CAUTION! Do not overtighten the nuts or damage to the mounting threads may occur.
Complete the LCD display replacement by proceeding to the Installing the Printed Circuit Board (page 4-7) section of
this chapter.