Scientific 5000 Series, Руководство пользователя

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7
– MAINTENANCE / TROUBLESHOOTING
MODEL 5000 SERIES MANUAL
Version 1.23
7-5
The extender board has test points for the voltages and IN and OUT bus signals on
the backplane. See Section 7.4.1 for proper voltages.
7.3.2 Replacing Components
Relays, op-amps and integrated circuits are all socketed for easy replacement. If
ordered, use the Component Level Spares Kit or Relay Spares Kit to replace possible
faulty components. If a spare part is not available, swap parts on a board to see if a
different error code follows the suspected bad part.
Note labeling on DIP relays. Most are „A‟ form relays, but a few are „C‟ form.
Hamlin/Clare HE731A12 are „A‟ form (black package), Coto 2712-12-0 are „C‟ form
(red package).
If faults have been cleared due to replacing an op-amp, it is important for at least
those boards that have been repaired to be calibrated to ensure that the instrument
conforms to specifications. Relay replacement does not affect calibration.
If, during servicing, a component needs replacing that is not socketed, it is
recommended that it be carefully de-soldered using either a vacuum de-soldering
pump or de-solder braid, taking care not to damage either the delicate copper trace
of the printed circuit board or adjacent components. It will often facilitate removal of
the leads if the component is first cut away and the sucked out from the circuit side.
The practice of attempting to solder a new component onto the remaining leads of
the old one is not recommended, as it is likely to cause poor mechanical and
electrical joints.
7.3.3 Block Tests
The mainframe self-test consists of blocks, each of which can produce one or more
error codes. To run an individual self-test block:
 “Runtime” – “Self-Test” – “System Block” menu.
 Enter the desired block number (or use “Up”, “Down” arrow keys)

Click the “Start” button
 The block number and either “PASSED” or “FAILED” will be displayed.
Definitions and theory of individual block tests follow the Self-Test Error Code Tables
(Table 7-10 through Table 7-15). Individual block tests can be used to diagnose a
fault if it is not cleared following parts replacement indicated in the Self-Test Error
Code Table. Each block definition shows an abbreviated schematic detailing those
items that are being tested. An explanation of each test and the fault condition for
each error code is included. Run the failed block test repetitively to diagnose the
fault. The waveform sketch included with each block is found on the IN bus, J1-31,
and identified on the Extender Board.
Trace the path shown confirming signals and relay conditions until the fault is found.
Extend the boards one at a time as required to trace the path. Always be sure cables
are properly attached to any extended boards before turning power on.
7.3.4 Fuses
If the error code calls for a fuse, replace with only the type specified.
AC Line: The two fuses protecting the incoming AC line are mounted
in the AC power receptacle mounted on the back panel.
They are type AGC slow-blow rated as follows: