GrayWolf IAQ SURVEYOR II, Руководство по эксплуатации

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48
MAN IAQ Surveyor Issue 11 2004
3. MICROMANOMETER AND THERMOCOUPLE
Notes: 1. Normally, the light colored, or clear, silicone tubing
is used for the positive pressure connection
(+VE) and the dark colored silicone tubing for the
negative pressure connection (-VE).
2. Ensure that the connections to both pressure
ports are of the same length and that the tubing is
neither kinked nor squashed.
3. To avoid any liquid or contaminant draining into
the pressure ports when making measurements
on saturated or dirty airstreams, use the full length
of the tubing provided with the instrument and
keep the instrument above the pressure tapping
point. If possible, allow the tubing to descend
below the level of the tapping point before rising to
the instrument.
Connect to the pressure ports as follows:
(1) For positive static measurements, connect the gauge
pressure tapping (for example, duct static, plenum
pressure and inlet cone depression), to the
+VE
port,
and leave the
-VE
port open to atmosphere.
(2) For negative static measurements, connect the gauge
pressure tapping to the
-VE
port, and leave the
+VE
port open to atmosphere.
(3) For differential pressure measurements (for example,
ori
fi ce plates, venturi devices, fl ow grids, valves,
diaphragms and fi lters) connect the upstream tapping
to the
+VE
port and the downstream tapping to the
-VE
port.
3.3.5 Volume Flow Rate
In order for the instrument to calculate volume fl ow rate from