Teledyne 3350 - Microprocessor based control room monitor for personnel safety - Manual (Page 24)

3 Installation Model 3350
3-8
Teledyne Analytical Instruments
The specific descriptions for each type of alarm are as follows:
Alarm #1 (CAUTION) Factory preset for OSHA Standards at 20%
Oxygen.
Alarm #2 (DANGER) Factory preset for OSHA Standards at 19.5%
Oxygen.
Sensor Fail Actuates when the output of the Micro-Fuel Cell sensor
falls below the acceptable level (0.05% Oxygen).
CAUTION: There could be hazardous voltage at the alarms termi-
nals, even when power is removed from the instrument.
Internal Sensor Wiring: The receptacle for the sensor cable is located
in the lower left-hand corner of the Control Unit rear panel. The 6-pin
polarized connector is keyed to fit only one way into the receptacle. Do not
force it in. The other end of the cable is connected to the top of the sensor in
the sensor housing
3.6 Calibration
Prior to operating this instrument for the first time, the Oxygen Monitor
must be calibrated. If this instrument is to be used as a safety monitor,
routine calibration should be carried out on a weekly basis.
If it is not feasible to use ordinary air as the calibration gas, then clean,
compressed instrument air can be used. It will probably be necessary to seal
the sensor in the piped-in calibration gas to isolate it from the surrounding
atmosphere. A flow-through adaptor can be purchased from TAI as an
accessory for those applications. Although a special calibration gas can be
used, the calibration results will be meaningless unless the oxygen concentra-
tion of the calibration gas is known, and the analyzer is adjusted to indicate
that concentration. To eliminate any error caused by the calibration gas,
always use a certified composition with an oxygen concentration between
80% and 90% of the full scale meter reading of the analyzer.
NOTE: Calibration in the same atmosphere that is being moni-
tored can result in serious error. The analysis per-
formed and the alarms, if any, generated by this instru-