Panametrics GF868, Руководство по обслуживанию

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DigitalFlow™ GF868 Service Manual (1 and 2-Channel) 43
Appendix B. Optional Enclosures
B.4 Rack Mount Option Card Installation
The Model GF868 flowmeter can accommodate up to six option cards in a manner similar to that used in a PC. The
option cards are installed into sockets on 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.
Refer to Figure 11 on page 50 and complete the following steps:
1. After disconnecting the main power to the meter, remove the top panel from the enclosure by removing the four
screws indicated.
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. By removing the screw
on the rear panel, remove the appropriate option slot cover to make room for the external connector on the new
option card.
4. To install the option card, insert its 32-pin connector into the chosen 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 option card is oriented with its external connector positioned in the opening on the rear panel.
5. Repeat steps 3 and 4 to install any additional option cards.
6. Place the metal bracket over the option cards, making sure that all installed option cards are inserted into the
plastic card guides in the bracket. The bracket must be oriented so that the six card guides are directly above the
six sockets on the printed circuit board (
do not install the bracket rotated 180° out of position). Secure the metal
bracket to the printed circuit board with the four plastic snap rivets provided.
7. After checking for any loose hardware that may have fallen into the enclosure, reinstall the top panel on the
meter and secure the panel in place with the four screws previously removed.
The Model GF868 flowmeter may now be placed back into service. Reconnect the main power and refer to Appendix
C,
Optional Enclosures, of the Startup Guide for instructions on wiring the new option card(s).
Note:
Be sure to record the option card installation in Appendix A, Service Record.
B.5 Rack Mount EPROM Replacement
The Model GF868’s User Program is stored on an erasable programmable read only memory (EPROM) chip. The
EPROM, which is designated as component U4, is located on the corner of the printed circuit board just behind the
keypad on the front panel.
EPROM replacement may be required to replace a defective chip or to upgrade to a newer software version. To
replace the EPROM, refer to Figure 11 on page 50 and complete the following steps:
WARNING! The main power to the Model GF868 must be disconnected before proceeding.
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.