GAS GC-IMS, User Manual

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GC-IMS
– User Manual
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6.6.4 Flow Ramps
The flow rate set points in a measurement program determine the target flow rates at
the specified time index. If set points differ from the default flow rate or varying flow
rate set points are specified in a program, the course of the actual flows will be
conducted as a linear ramp of the flow. Starting point of the ramp is the latest set
point. If no earlier set point is given the ramp starts with program initialization using
the default set point.
An exemplary program using a dynamic flow rates is visualized in the following
figure:
Figure 46: Flow Ramps
The E2 (carrier gas flow) value is initially set to 10ml/min. The flow is kept constant
for one minute. Between runtime 1min
– 5min the flow is linearly increased to the
target value 100ml/min. In the following the flow is increased linearly to 150ml/min in
one minute.
INFORMATION!
Before starting a measurement make sure that the highest flow set
points can be achieved. Note that large changes in the flow set
points will need finite time.