Section 5. SAFETY AND MAINTENANCE CHECKS
The LC-22C, LC-23A, LC-23C and cell preheater are all essentially maintenance free
instruments. BAS does advise that you attempt to keep these pieces in good condition by
following these suggestions:
1.
Avoid corrosive laboratory environments.
2.
Don’t stack heavy items on signal cables or allow them to become crimped during use
or storage.
3.
Clean up spills inside column heaters immediately.
4.
Avoid contact of organic solvents with the insulating material inside the LC-23C cover.
The Universal Probe is based on a reliable solid state device capable of generating a
predictable current related to the temperature of its environment. To check the integrity of
this probe, apply the following test:
1.
Expose probe to ambient temperature and disconnect any heating devices from the
LC-22C.
2.
Turn on the LC-22C power.
3.
Set the temperature setpoint to a value greater than ambient (allow at least 1°C difference).
The “HTR” LED indicator on the LC-22C should be on continuously.
4.
An open circuit anywhere in the probe, cable or across its input jacks will automatically
shut down the heater circuit. This feature was incorporated to protect against thermal
“runaway” and should be tested periodically. Perform the following check:
A.
Plug in the probe, expose to ambient air temperature and turn on the
power to the LC-22C.
B.
Create an open circuit in the probe by unpluging the red or yellow lead
from the chassis jacks on the LC-22C. Using the digital display
selector knob, illuminate the tested channel “SENS 1" or ”SENS 2"
LED. A digital reading of approximately .3.9.8 degrees (-13.98 volts at
the OUTPUT screw terminals) will be shown. Note that the left, center
and right decimal points are illuminated indicating an open circuit.
C.
Remove the probe entirely and place a jumper cable across the red and
yellow PROBE INPUT jacks to create a closed circuit. A digital reading
of approximately 2.7.9 degrees (+12.79 volts at the OUTPUT screw
Section 5. SAFETY AND MAINTENANCE CHECKS
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