LumaSense Technologies INNOVA 1303 - Manual (Page 36)

Chapter 3
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BE1085-14
1303 Multipoint Sampler and Doser LumaSense Technologies A/S
Page 36 of 60
MAIN_DOS_VALVE OP<LF> Opens the main dosing valve to al-
low the flow of tracer-gas to the
dosing valves.
The main dosing valve will close automatically to protect the doser-
system airways if the tracer-gas pressure in the dosing manifold is
above 550 kPa absolute.
3.6.3 Starting Continuous Dosing
Using the interface job described below starts an uninterrupted flow of
tracer-gas through the specified dosing valves. Any number of the dos-
ing valves can be opened simultaneously. The valve specified in the in-
terface job will be opened; those not specified are closed. The 1303’s
doser system is also equipped with a pump which pumps carrier-air
through the dosing valves to accelerate delivery of the tracer-gas to the
dosing points. The dosing pump is controlled separately from the dos-
ing valves.
Note: the carrier-air inlet on the rear panel of the 1303 must not be
blocked.
Example:
OPEN_DOSING_VALVE
1,2<LF>
Opens only dosing valves 1 and
2. If no dosing valves are speci-
fied, all dosing valves are closed.
The dosing pump must then be started. The pump is controlled using
the following commands.
DOSING_PUMP ON<LF> Starts the carrier-air pump.
DOSING_PUMP OFF<LF> Stops the carrier-air pump.
If no further instructions are sent to the 1303, the dosing procedure
will be stopped automatically when the time-period specified by the
Dosing Time-out parameter,
section 3.3.1 , has elapsed. To continue the
task in progress, the same job should be sent again to the 1303 before
the dosing time-out period has elapsed.
The carrier-air pump can be used to effect air-change in the casing of
the 1303, to prevent a build-up of the concentration of tracer-gas in
the casing of the 1303. This is done using the interface job DOS-
ING_PUMP AUTO. When sent to the 1303, this job causes the doser
pump to start automatically whenever the pressure in the 1303’s doser