2.2.2 Description of equipment function
The devices of the type 2240 PROcheck are primarily intended for
measurement of gas concentrations in fumigation processes. They are
equipped with 3 measuring gas connections, which can be selected
either by the instrument software automatically or by an external
controller (Plant- or machine-control). Two limits per channel can be
adjusted to suit your requirements independently.
For measuring the gas concentration of the currently selected
measurement channel, the gas to be analysed is drawn by the device
internal diaphragm pump through a particulate filter and the sample
gas line in the sensor (active sampling). During the measuring
operation a large number of individual measured values is integrated.
The result is continuously displayed and compared with the limiting
values valid for the current measurement channel.
A comparison of the set limits versus measured value will be executed
only after a predetermined time (set by device software) to avoid
mispricing by short-term fluctuations in concentration. The formation
of mean values for the storage (USB / GSM) begins just after this time
has elapsed.
The “traffic light” indicator on the front panel visually inform about
the status of the measuring channel with respect to the set limits.
For the behavior of the alarm contacts are three settings available:
NO
(normally open)
NC
(normally closed)
Alarm window
The following tables describe the status of the LED lights and the
signal contacts with different alarm settings.
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