LumaSense Technologies INNOVA 1303 - Manual (Page 9)

Chapter 1
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BE1085-14
1303 Multipoint Sampler and Doser LumaSense Technologies A/S
Page 9 of 60
1.1.1 The Sampler System
The pneumatic system of the 1303 is shown schematically in Fig. 1.1 .
The sampler system is constructed of 316 stainless steel and PTFE (Poly
Tetra Fluoro Ethylene) tubing to minimize adsorption of samples. The
system has 6 inlet channels, each with a solenoid valve. Each inlet
channel has a tube-mounting stub on the front-plate of the 1303; 6
tubes of up to 50m length connect each channel to the respective sam-
pling point. The 6 inlet channels converge into one; a three-way valve
can then direct the gas sample to the Gas Monitor for analysis, or
through the pump to the waste-air outlet on the 1303’s back-plate. A
pressure transducer checks the efficiency of the sampling pump and al-
lows checks for blocked airways.
An air-filter is attached to the end of each sampling tube to keep the
samples free of particles.
1.1.2 The Doser System
The doser system has 6 outlet channels, see Fig. 1.1, each with a sole-
noid valve. Each channel has a nozzle which reduces the internal diam-
eter of the channel. The nozzles ensure that the rate of flow of tracer-
gas to the dosing points is dependent only upon the tracer-gas supply
pressure and temperature, and is unaffected by the pressure in the
dosing tubes or at the dosing point itself. Three different nozzle sizes
are used: four medium, one large and one small. Each size gives a dif-
ferent volume flow rate so that the amount of tracer-gas delivered to a
particular dosing point can be matched to the requirement at that point
by using the outlet channel which has the appropriate nozzle.
Each of the 6 dosing outlet channels has a tube-mounting stub on the
front plate of the 1303. 6 tubes of up to 50m length connect each stub
to the respective dosing point.
2 separate inlet channels mounted on the back plate of the 1303 serve
the dosing channels: the tracer-gas inlet, and the carrier-air inlet.
The doser-gas inlet channel is pressurized by the tracer-gas supply cyl-
inder, which is connected to the inlet on the 1303’s back plate by tub-
ing. A pressure and a temperature transducer give information on the
tracer-gas supply; a fine filter ensures that the dosing channels are
particle-free. The main valve on the tracer-gas inlet channel is used to
enclose a volume of tracer-gas between itself and the dosing valves.
This volume is used when calibrating the doser system.