SRS Labs CTC100, User Manual

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Operation 76
CTC100 Programmable Temperature Controller
repair or replace an I/O card or the CPU card, the following process can be
used to remove the card from the chassis:
1. Unplug the instrument and remove the top lid.
2. Carefully remove the bottom lid. After removing the four screws, pull the lid about an inch
away from the case and look for the fan mounted on the lid and connected to the front
panel. You'll need to unplug the fan before the lid can be completely removed. It's difficult
to reach the plug since it's at the top of the front panel, behind the big silver power supply.
For better access it may be necessary to remove two of the screws that hold the power
supply in place (the top screw on the left and right sides of the case) so that the power supply
can be rotated out of the way.
3. Remove the screws on the left and right sides that are normally covered by the bottom lid.
These screws are only needed for shipping; if you're not going to be shipping the instrument
anywhere, they don't need to be re-installed when you re-assemble the chassis.
4. Look at the bottom of the instrument. You should clearly see the bottom of the backplane
card, which is the largest card in the instrument and the only one that's mounted
horizontally. At the edge of the backplane card closest to the display are two screws.
Remove these two screws. These screws are only needed for shipping and don't need to be
re-installed when you re-assemble the chassis.
5. On the back panel, use a deep 9/16 inch socket wrench to remove the 4 BNC nuts on the
analog I/O connectors.
6. Remove the 4 screws or nuts above and below the RTD/thermistor/diode inputs. It's
especially important to re-install these screws when re-assembling the instrument. Without
these screws, the input connectors will not be grounded and
temperature
readings will be inaccurate due to electromagnetic interference.
7. Remove the 2 screws at the top of the back panel above the big vent.
8. Remove the 1 screw just below the words "AC power 88 264V 4A".
9. Remove the 2 nuts above and below the DIO port.
10. If the instrument has a GPIB port, remove the 2 nuts above and below the GPIB port.
11. At this point, only the screws for the heater driver terminals and the RS-232 port (if the
instrument has an RS-232 port) should remain on the back panel. Do not remove these
screws.
12. Push the entire card and backplane assembly away from the back panel by about half an
inch. Usually the best way is to gently push on the In 1 & 2 port with one thumb and on the
DIO port with the other, but make sure not to apply so much force that you bend the
connectors.
13. It should now be possible to pull the I/O or CPU card out.