TM 10-6665-297-13&P
3-2.2
Calibrating a System with Two Detectors per CD800/830 Control Unit (continued)
If using J-W Calibration Kit(s) 0023-7260: 2 Gas Calibration Cylinders: Either 100% Nitrogen (0023-
4003) or Zero Gas/Dry-air (0023-4004) if combustible-gas-free air does not exist at both detectors
(one or none required if one or both detectors are in fresh air. If Professional Calibration Kit(s) (51-
7070) is used, kit supplies clean, filtered air for zero calibrations.
If using J-W Calibration Kit 0023-7260: Gas Calibration Cylinder containing sample gas similar to that
expected at detector locations. If using Professional Calibration Kit 51-7070: Kit supplies sample gas
at known percent L. E. L. concentration.
0-10 Volt range D. C. voltmeter with ± 2% accuracy in 5-6 Volt range.
Test Socket Adapter 0023-4027
Circuit Card Extender 0023-4023 (except for CD800P models with built-in extension feature)
Calibrate CD800/830 paired-detector alarm system for zero meter indication in gas-free air as follows:
1.
Read supply voltages at both detectors (using test socket adapter and voltmeter in accordance with
instructions in Section 2-6.7.
2.
If supply voltages are not within 0. 15 VDC at both detectors, find and correct faulty circuit
conditions (poor connections, leakage, open or short circuits, unbalanced resistances in supply lines
due to wrong choice of wire gauges for length of run). Remove test socket adapter(s) and reinstall
sensor elements in detector socket(s).
3.
Using portable combustible gas indicator, test surrounding air at both detectors. If combustible gases
are present at one or both detectors, use J-W gas calibration kit(s), sample cup(s), and 100%o
Nitrogen or Zero-gas/Dry-air cylinder(s), or Profession Calibration Kit(s) 51-7070 to supply
combustible, gas-free air (paragraph 3-1.1, Figure 3-1, and Professional Calibration Kit instructions
51-9001).
NOTE: Both detectors must be sampling zero combustible gas before adjustment of indicating
meter circuitry for zero meter setting.
4.
For access to control unit screw adjustments in many rack and cabinet installations, remove circuit
board, plug circuit card extender #0023-4023 into connector strip at rear, and plug circuit board into
card extender. Use of the card extender during circuit adjustments prevents remote alarms from
operating.
23-9617
4/6/77
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