Operating instructions

AMC-DTR Sensor Transmitter User Manual
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higher value in order to achieve the correct voltage at the sensor. Correct sensor voltage
should be confirmed after start-up for locally and remotely mounted catalytic bead sensors.
5.2.2 Initial Catalytic Bead LEL Monitor “Balance” Check
Catalytic bead sensors connect to a bridge circuit that may require a balance adjustment after
installation especially when the sensor is remote mounted from the AMC-DTR. Correct
BALANCE setting should be confirmed after start-up for locally and remotely mounted catalytic
bead sensors.
5.2.3 Initial Catalytic Bead LEL Monitor “Span” Check
Prior to the initial Routine Sensor Calibration described in section 6.1, a coarse SPAN gas
reading verification should be performed after installation. After correct Sensor Volts and
BALANCE have been verified, apply an upscale gas value such as 50% LEL to the sensor. The
indicated value should read between 35 and 65% LEL with 50% LEL gas applied. Larger errors
may indicate incorrect sensor wiring or defective sensor. Remember that this is only a coarse
check and precision calibrations are performed in Routine Sensor Calibrations described in the
following section 6.1.
5.3 Initial Toxic / Oxygen Monitor Start-Up
AMC-DTR Toxic / Oxygen Monitors, are factory equipped with a local Simple or Smart
electrochemical sensor, rarely require adjustments (other than routine calibrations) to provide
accurate readings. However, after installation the following checks should be performed to
insure proper operation. In addition, alarm levels, Measurement Name ASCII fields and other
variables may require attention by users in order to best serve their application.
5.3.1 Initial Toxic / Oxygen Monitor “Span” Check
Prior to the initial Routine Sensor Calibration described in section 6.1, a coarse SPAN gas
reading verification should be performed after installation. Apply an upscale gas value of at
least 25% of full scale to the sensor. For example, if 0-100ppm H2S is the measurement range,
apply at least 25ppm but not more than 100ppm. The indicated value should read within 15% of
full scale. Remember that this is only a coarse check and precision calibrations are performed
in Routine Sensor Calibrations described in the following section 6.1.