Panametrics DigitalFlow GC868, Руководство по обслуживанию, Страница: 50 / 64

Appendix B. Optional Enclosures
B-1 DigitalFlow™ GC868 Service Manual (1 and 2-Channel)
B.1 Introduction
The Model GC868 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 GC868 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 (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
GC868.
B.2 Rack Mount
Enclosure
Refer to Figure B-1 on page B-8 and Figure B-2 on page B-9 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.
B.3 Rack Mount
Fuse
Replacement
If it has been determined that the fuse in the Model GC868 requires replacement,
refer to Figure B-1 on page B-8 and Figure B-2 on page B-9, and complete the
following steps:
1. On the rear panel of the meter, set the power switch to the OFF position and pull
the power cord out of its receptacle.
2. Locate the black plastic fuse cover on the back panel at the bottom of the power
cord receptacle and pull it straight out.
3. Replace the defective fuse with a new one of the same rating and type. Use only
5 x 20 mm Slo-Blo fuses, having a rating as indicated in Table B-3 below and on
the rear panel label.
WARNING! Prior to performing any maintenance procedures,
disconnect the main power from the unit.
WARNING! The main power to the Model GC868 must be
disconnected before proceeding.