DigitalFlow™ GF868 Service Manual (1 and 2-Channel) 33
Chapter 4. Parts Replacement
4.5 Installing an Option Card
The Model GF868 flowmeter can accommodate up to six option cards. The option cards are installed into sockets on 
the rear of the printed circuit board, and they are held in place with a metal bracket. A single metal bracket is used to 
secure all the installed option cards.
Note: If the Model GF868 presently has no option cards installed, be sure to purchase the metal mounting bracket 
along with the first option card.
To install an option card, refer to Figure 9 on page 38 and complete the following steps:
1. Remove the printed circuit board, as described in a previous section of this chapter.
2. If one or more option cards are already installed, remove the four fasteners that secure the metal bracket to the 
printed circuit board. Lift the metal bracket straight up and away from the printed circuit board.
Note:  The fasteners may be either plastic snap rivets or metal hardware (in some older meters). In either case, they 
may be discarded, as new plastic snap rivets will be provided.
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.
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. Refer to 
the installed assembly in Figure 8 on page 37.
Complete the option card installation by proceeding to the Installing the Printed Circuit Board section of this chapter.
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.