AMC AMC-360-IREP 사용 설명서 - 페이지 13
{카테고리_이름} AMC AMC-360-IREP에 대한 사용 설명서을 온라인으로 검색하거나 PDF를 다운로드하세요. AMC AMC-360-IREP 16 페이지. Infrared methane sensor/transmitter 0-100% lel range
AMC-360-IREP 0-100% LEL Methane Sensor/Transmitter
5.2.2 TRANSMITTER CALIBRATION / VERIFICATION SET-UP PROCEDURE
The calibration procedure may cause the monitoring equipment to give a false alarm, therefore
appropriate precautions should be taken. Refer to Figure 5 for the following procedure.
1. Remove cover from transmitter housing
2. Connect "Remote Calibration Lead" to multimeter.
BLACK lead to negative or common (–).
RED lead to positive (+).
3. Switch ON multimeter and select the 200 mA DC milliamp range to allow readings
greater than 20 mA full scale.
4. Insert plug end of "Remote Calibration Lead" fully into CAL jack on transmitter cover
plate. This will block the outgoing signal, causing a "fail" at the monitor.
5. With the sensor in clean air or zero gas, check for a stabilized zero signal of
approximately 4.0 mA.
6. Apply a Span gas sample delivered at a flow rate of 0.5 to 1 litre per minute. Since the
transmitter output range is 4 to 20 mA, a full-scale concentration should register 20 mA
after a few moments exposure. Proportionately, a half-scale concentration of gas should
register 12 mA, and so on.
5.2.3 ADJUSTMENTS (STANDARD CALIBRATION)
For full recalibration adjustments, follow the set-up procedure steps 1 to 6 inclusive. There are
two adjustments to be made for recalibration, Zero and Span.
•
ZERO: When there is no gas present (clean air), the transmitter signal should be 4 mA.
This is obtained by adjusting the zero trimmer on the transmitter. It is possible, with
certain conditions, that the "zero" current will go below 4.0 mA.
•
SPAN: When the sensor is exposed to the calibration gas sample, adjust the span
trimmer on the transmitter to set up the output current proportional to the gas
concentration applied.
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