Teledyne 9110AH Instruction Manual page 160

TELEDYNE Model 9110AH NO
The thermocouple amplifier for the converter temperature has a gain adjustment. The voltage
across J2 reads 27.5 mV when the converter temperature is 700 C. The CPU is programmed to
always drive the temp to 700 C, so the thermocouple voltage must be used as the absolute
reference as to the correct temperature.
The temperature can be adjusted by the R6 pot. To adjust the converter temperature:
1. Select the CONV TEMP - TEST function on the front panel.
2. Wait until the converter is up to temperature, usually 30-45 min after a cold start.
3. Adjust R6 until the front panel readout equals 700 C for the CONV TEMP and the voltage at
J2 is 27.5 mV.
4. Recheck the two readings 15 min later and re-adjust if necessary.
9.3.4.2 Display Brownout
During low AC line conditions the display can lock up due to insufficient voltage. When low
line conditions are approaching, this circuit senses the condition by monitoring the un-regulated
+5 VDC in the Power Supply Module. If brownout conditions are met, the DISP_BROWNOUT
line is asserted and the CPU sends a hardware RESET command to the display and sends a
BRNOUT RESET pulse back to U4. Brownout conditions will be noticed by the display
flashing every 8 seconds.
9.3.4.3 Status Output Lines, External Contact Closures
The Status lines consist of 4 active input lines, and 12 active output lines. Individual lines are
set or cleared under CPU control depending on the assigned alarm condition. The CPU also
monitors the 4 input lines for remote calibration and range control commands. The status inputs
and outputs are terminated at the rear panel, see the schematic in the Appendix.
The output lines are opto-coupled NPN transistors which can pass 50 ma max of direct current
with a voltage of 30 VDC max.
The input lines are optically coupled with inputs pulled up to +5 VDC. External contacts can be
contact closures or open collector transistor contacts. DO NOT apply any voltage, since +5
VDC is supplied internally.
Individual status lines can be set or cleared using the DIAGNOSTIC mode SIGNAL I/O. This
can be useful for simulating fault conditions in the analyzer to see if external circuitry is
working correctly. See Table 5-8 for pin assignments.
Analyzer Operator Manual, 01620, Rev. F
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