UNITED Nitrogen Pac SC-W, Установка, наладка, обслуживание

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5. FACTORS INFLUENCING ACCURATE READINGS
Elevation Changes : Changes in elevation result in a reading error of approximately 1% of reading per
250 feet. In general, calibration of the instrument should be performed when elevation at which the
product is being used changes by more than 500 feet.
Temperature Effects : The N
2
analyzer will hold calibration and read correctly within ±3% when in
thermal equilibrium within the operating temperature range. The analyzer must be thermally stable
when calibrated and allowed to thermally stabilize after experiencing temperature changes before
readings are accurate. For best results, perform calibration at a temperature close to the temperature
where the analyzer will be used.
“
CAL Err St
” may be displayed if the analyzer has not reached
thermal equilibrium.
Pressure Effects : N
2
analyzer readings are proportional to the oxygen partial pressure. Partial
pressure is concentration multiplied by absolute pressure. Thus, if pressure is constant, readings are
proportional to the oxygen concentration. For best results:

Calibrate the analyzer at the same pressure as the sample gas.

The oxygen sensor is intended for use up to two atmospheres absolute pressure. Use the analyzer
within this parameter.
Humidity Effects : Non-condensing humidity (up to 95% RH) should have no significant effect upon
analyzer performance (other than possibly diluting the sampled gas up to 4%, proportionately
reducing the oxygen concentration). For best results:

Do not use the analyzer in environments where condensation may occur. Condensation can block
the sampling tubing, resulting in erroneous readings and slower response time.

Avoid use of the analyzer in environments greater than 95% relative humidity.
6. CALIBRATION ERRORS AND ERROR CODES
The N
2
analyzer has a self-test feature built into the software to detect faulty calibration, oxygen
sensor failures, and low operating voltage. These are listed below, and include possible actions to take,
if an error code occurs.
E03 : No valid calibration data available: Make sure the analyzer has reached thermal equilibrium.
Press and hold the Calibration button for three seconds to manually force a new calibration.
E04 : Battery below minimum operating voltage : Unit is at end of life. See Section 9 for proper
disposal.
CAL Err St : O2 Sensor reading not stable. Wait for displayed oxygen reading to stabilize when
calibrating the analyzer at 100% oxygen. Wait for unit to reach thermal equilibrium. (Please note that
this can take up to one half hour, if the analyzer is stored in temperatures outside the specified
operating temperature range.)
CAL Err lo/hi : Sensor voltage too low/high
:
Press and hold the Calibration button for three seconds
to manually force a new calibration. If unit repeats this error more than three times, contact UNITED
Fire Systems for possible sensor replacement.
CAL Err Bat : Battery voltage too low to recalibrate
.
Analyzer is at end of life. See Section 9 for
proper disposal.