Panametrics CTF878, Service Manual

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Model CTF878 Service Manual 41
Chapter 5.
5.1.5 Installing the Printed Circuit Board
Whether the printed circuit board was removed for replacement or for one of the other procedures discussed in this
chapter, reinstallation of the printed circuit board is the final step in the process. Refer to Figure on page 43 and
Figure 1-2 on page 11, and complete the following steps:
CAUTION!
During this procedure, be very careful not to damage the vertical components along the top edge of
the printed circuit board. Severe or repeated bending of these components will break their leads.
1. Carefully position the printed circuit board within the electronics console, up against the nine standoffs in the
enclosure. Do not damage the transformers and any installed option cards as they are maneuvered between the
standoffs.
2. Loosely install the three standoffs on the right side of the printed circuit board and the two standoffs along the
bottom edge. Then, install the two mounting screws (just left of center) and the top and bottom standoffs on the
left side.
3. Securely tighten all nine standoffs and/or screws.
4. Connect the twisted-pair backlight cable to socket J6 . This plug is polarized so that it can only be installed in the
proper orientation, with the black wire above the red wire.
5. Connect the keyboard cable to socket J5 and the display cable to socket J7 .
6. Check for and remove any loose hardware that may have fallen into the electronics console during the
maintenance procedure.
7. Place the main shroud over the five upper standoffs on the printed circuit board. Making sure that the shroud is
oriented with the wiring diagram label upright, fasten the shroud to the standoffs with the five sets of screws and
washers.
8. Reconnect the power line wires to terminal block TB1 on the printed circuit board. Plug all other electrical
connectors into the appropriate sockets on the printed circuit board and option cards. See Installation, Chapter 2
of the Startup Guide for instructions on proper wiring of the CTF878.
9. Position the clear plastic LVD shroud over the electrical connections so that the two holes in the shroud align with
the standoffs on the printed circuit board. Secure the shroud to the standoffs with the two sets of screws and
washers.
10.
After carefully checking for and removing any loose hardware in the enclosure, close the electronics console and
reconnect the main power to the CTF878.
Note: For compliance with the European Union’s Low Voltage Directive (2006/95/EC), this unit requires an external
power disconnect device such as a switch or circuit breaker. The disconnect device must be marked as such,
clearly visible, directly accessible, and located within 1.8 m (6 ft) of the CTF878.
Before taking measurements with the CTF878, refer to
Initial Setup, Chapter 3 in the Startup Guide, and to Calibration,
Chapter 3 in this
Service Manual, for instructions on properly setting up the meter for accurate flow rate
measurements.
Note: Be sure to enter a complete and detailed account of the service procedure performed on the CTF878 in
Appendix A, Service Record.