Chapter 4. Parts Replacement; Introduction - GE DigitalFlow DF868 Service Manual

Chapter 4. Parts Replacement

4.1 Introduction

The electronics console of the Model DF868 has been designed to permit easy on-site upgrades and parts replacement.
See Figure 8 on page 35 and Figure 9 on page 36 for details of the standard DF868 electronics console assembly. The
instructions in this chapter, along with a few common tools, are all that is required to perform the following tasks:
•
fuse replacement
•
printed circuit board (PCB) removal and installation
•
EPROM replacement
•
option card installation
•
LCD display replacement
IMPORTANT: For meters supplied in any of the optional enclosure types, see Appendix B, Optional Enclosures, for
instructions specific to that unit.
WARNING! Prior to performing any maintenance procedures, be sure to disconnect the main power from
the unit.
Note: For compliance with the European Union's Low Voltage Directive (73/23/EEC), 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 Model DF868.
An aluminum shroud over the printed circuit board shields the electrical components and serves as a location for the
wiring diagram label. All of the procedures discussed in this chapter, except for fuse replacement, require removal of
this shroud.
Note: For compliance with the European Union's Low Voltage Directive (73/23/EEC), a transparent plastic shroud
protects the electrical connections. The shroud must remain in place, except while wiring the unit. Reinstall the
shroud after the wiring has been completed.
Use the foldout drawings at the end of this chapter to locate the relevant components, while completing the following
procedures.
IMPORTANT: Keep a detailed record all service procedures performed on the Model DF868 in Appendix A, Service
Record. This service history may prove very helpful in diagnosing any future problems.
DigitalFlow™ Multipurpose Ultrasonic Liquid Flowmeter Service Manual
Chapter 4. Parts Replacement
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