Servomex SERVOTOUGH LaserExact 2950, Operator'S Manual

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SERVOTOUGH LaserExact Monitor, Operator Manual 02950001A_1
32 C
HAPTER
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Instrument time
The instrument has a built-in clock, which also runs when power is off. Using this
menu the instrument time should be set equal to the local time. The current
instrument time is only downloaded from the instrument after an update of
parameters or explicitly after pressing <Reload readings (P, T, date)>.
Extra (flow) current input select
Configures the extra (denoted as “Flow”) current input to the instrument. It can be
set to “None”, “Gas - % vol”, “Gas - g/Nm3”, “Gas – g/m3”, and “Flow”. Input
“None” simply deactivates the extra current input. For all other inputs the 4 mA and
20 mA values must be specified. The current input can be used to connect an
external gas sensor (typically an H
2
O sensor for dry basis conversion) to the
instrument. In this case “Gas” input with the corresponding concentration unit
should be selected. The measured input current can be monitored in the
Measurements menu.
Input “Flow” is currently not implemented.
Dry basis conversion
The primary measurements of the gas concentration are on wet basis, except if
moisture is removed by a sampling system installed between process and
analyser. The instrument can also present the results on dry basis if the H
2
O
concentration is known. If <Dry basis conversion> is selected the instrument
converts the measured concentrations according to the following simple equation:
N(dry) = N*100 / (100- H
2
O(%))