6 using the doser system – LumaSense Technologies INNOVA 1303 User Manual
Page 35
Chapter 3
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BE1085-14
1303 Multipoint Sampler and Doser
LumaSense Technologies A/S
Page 35 of 60
limits. The pressure across the sampling pump can be checked to en-
sure efficient gas-transport; see
section 3.8.1
for details.
The sampling pump can be controlled using the following jobs:
SAMPLING_PUMP ON
SAMPLING_PUMP OFF
3.6 Using the Doser System
The 1303 can perform two types of dosing tasks: continuous, which
gives an uninterrupted flow of tracer-gas over a period of time; or dis-
continuous, where the flow of tracer-gas is interrupted at regular inter-
vals during a given dosing time. These tasks are dealt with in turn be-
low.
Before starting any dosing tasks, the 1303’s doser system (see
Fig.1.1
)
must be calibrated with the tracer-gas to be used – see
section 3.4
for
details of how to do this. The 1303 cannot open a dosing valve for
which calibration data does not exist.
To ensure efficient dosing, the tracer-gas pressure must be in the range
300 kPa to 450 kPa absolute.
3.6.1
The Dosing System
Flushing Recommendation
After the Type 1303 has been used for dosing, it should be flushed
through with nitrogen gas. This can be done using the “Flush Function”
featured in Type 7620 Application Software.
Releasing the Pressure
The pressure inside the 1303 must be released before storage. This can
be done by closing the valve to the dose-gas bottle, or by removing the
tube supplying the dose gas to the 1303 while it is dosing.
Failure to release this pressure can result in the piston inside the dosing
outlet valve(s) becoming stuck to the rubber seal. This can result in the
valve having difficulty opening the next time the instrument is used.
3.6.2
Opening the Main Dosing Valve
The main dosing valve (see
Fig.1.1
), which isolates the tracer-gas sup-
ply from the internal airways of the 1303, must first be opened.
Example: