Assessments - 4, GPA: 4.5
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Facilidade de uso
Refer to Figure 4-1. 1) Gently turn the valve counterclockwise. A stream of bubbles should appear at the base of the humidifier column, and the float of the flowmeter should rise in its tube. 2) Adjust the valve so that the flowmeter float is centered in the flow rate reference indicator. CAUTION: Open the throttle valve carefully. Excessive flow rate may cause water in the humidifier column to be carried into the detector cell. This can cause erratic readings and may require disassembly, cleaning, and refilling of the sensor. 3) The flowmeter indicator has been factory set to a flow rate of 150 cc/min 150 cc/min150 cc/min150 cc/min150 cc/min150 cc/min. for the specified sample gas. CAUTION: Excessive flow rate may cause water in the humidifier to be carried to the flowmeter causing moisture to accumulate. This can cause the ball to stick in the flowmeter. To remove moisture, remove the flowmeter and allow to air or blow dry. Refer to the detailed instructions in Figure 5-2 for removal and installation of the column. 4.4 4.44.44.44.44.4 Humidity Control Humidity ControlHumidity ControlHumidity ControlHumidity ControlHumidity Control The humidity control is located on the front panel of the control unit, and is adjusted to maintain a constant electrolyte level in the detector cell. In effect, the control governs the humidity of the sample which is directed to the cell. Teledyne Analytical Instruments 4 44444 Operations OperationsOperationsOperationsOperationsOperations Model 356W Model 356WModel 356WModel 356WModel 356WModel 356WA AAAAA Outside Electrode Connected to "Y" Terminal Post (+) Oxygen Generated Here Electrical Terminal Board Sub-Assembly O-Ring Wick Saturated With KOH Electrolyte Solution Inside Electrode Connected to "B" Terminal Post (-) Hydrogen Generated Here Figure 8: Calibrator Assembly Teledyne Analytical Instruments T TTTTTrace Oxyg race Oxygrace Oxygrace Oxygrace Oxygrace Oxygen Anal en Analen Analen Analen Analen Analyz yzyzyzyzyzer ererererer Operations OperationsOperationsOperationsOperationsOperations 4 44444 1) At start-up, the humidity control knob should be set to 30 3030303030. Note the cell electrolyte level as a reference. Approximately 3/32" of the bottom edge of the screen assembly should be immersed in the electrolyte. 2) Operate the analyzer for 24 hours and compare the electrolyte level with the “reference” established in Step 1. If the level is lower than the reference, adjust the knob a few divisions clockwise; if higher, adjust a few divisions counterclockwise. 3) Operate another 24 hours and repeat Step 2. 4) Continue adjustments at ever-increasing intervals until a constant electrolyte level is attained in the cell. Once the analyzer is suitably located, all components serviced and installed, and sample and electrical connections made, the instrument is ready for operation. 4.5 4.54.54.54.54.5 Power PowerPowerPowerPowerPower When power is turned on, power is applied to the cell compartment heater. The cell operates without applied power, but its output will vary with changes in ambient temperature. 4.6 4.64.64.64.64.6 Warm-Up and Stabilization Warm-Up and StabilizationWarm-Up and StabilizationWarm-Up and StabilizationWarm-Up and StabilizationWarm-Up and Stabilization When the analyzer is initially put into operation, the air in the lines and sample passages will drive the output indication to the top of the scale. The time required to sweep out this residual air may be several hours before an on-scale indication is reached. During this time the cell compartment is heating and reaching its controlled temperature. 4.7 4.74.74.74.74.7 Calibration CalibrationCalibrationCalibrationCalibrationCalibration The analyzer is calibrated by adding a known amount of oxygen into the analyzer by means of a calibrated span gas. The sensitivity of the analyzer is adjusted until the change indicated by the analyzer is equal to the amount of oxygen known to be present in the span gas. The span gas must be composed of the same elements as the specified sample gas if the analyzer's calibrated flowmeter is to be used. TBE/AI recommends that the oxygen content of the span gas be between 70–90% of full scale on the range of interest. Teledyne Analytical Instruments 4 44444 Operations OperationsOperationsOperationsOperationsOperationsModel 356W Model 356WModel 356WModel 356WModel 356WModel 356WA AAAAA To calibrate the analyzer: 1. Shut the sample gas off, disconnect the sample in line and connect the the span gas to the sample inlet. Allow the span gas to flow through the system. Adjust the span gas flow rate until the flowmeter float is centered in the flowmeter reference indicator. Note the reading of the external recorder or meter. 2. Turn the range selector switch to the range which encompases the oxygen concentration of the span gas. The meter or recorder should move upscale and indicate the exact concentration of oxygen in the span gas. 3. If the external recorder/meter does not indicate ...