Panametrics DigitalFlow GM868, Руководство по обслуживанию

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DigitalFlow™ GM868 Service Manual 43
Appendix B. Optional Enclosures
Appendix B. Optional Enclosures
B.1 Introduction
The Model GM868 is available in optional enclosure types, each of which has been designed to permit easy on-site
upgrades and parts replacement. See the foldout drawings at the end of this appendix for details of the applicable
GM868 electronics console assembly. The instructions in this appendix, along with a few common tools, are all that is
required to perform the following tasks:
• fuse replacement
• option card installation
• EPROM replacement
• LCD display replacement
• printed circuit board (PCB) replacement
IMPORTANT: For meters supplied in the standard Type-4X enclosure, see Chapter 4, Parts Replacement, for
instructions specific to that unit.
Note: For compliance with the European Union’s Low Voltage Directive, 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 GM868.
B.2 Rack Mount Enclosure
Refer to Figure 10 on page 51 and Figure 11 on page 52 for the location of the relevant components, while completing
the following procedures. If the top panel of the meter is accessible, service may be performed without removing the
meter from the rack. Otherwise, disconnect all rear panel electrical connections and remove the meter from the rack
before proceeding.
IMPORTANT:
Keep a detailed record of all service procedures in Appendix A, Service Record. This record may prove
very helpful in diagnosing any future problems.
WARNING! Prior to performing any maintenance procedures, disconnect the main power from
the unit.