Tisch Environmental PUF+, Operator'S Manual

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PUF+ Operator’s Manual Tisch Environmental
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“AutoCal” Pressure
The “AutoCal” pressure port is used to make the Pcal measurement. It should be
connected to the calibrator during the AutoCal procedure.
“Ambient” Pressure
The “Ambient” pressure port is used to make the Pamb measurement. It should be
left open to atmosphere so that it properly senses the ambient pressure.
“O” Pressure
The “O” pressure port is used to make one half of the Pdif measurement. It
should be connected to the upstream port of the orifice (upper most port). Both “O”
and “Orifice –” must be connected to the orifice for proper flow measurement.
“Orifice –” Pressure
The “Orifice –” pressure port is used to make one half of the Pdif measurement. It
should be connected to the downstream port of the orifice (lower most port). Both “Orifice
+” and “Orifice –” must be connected to the orifice for proper flow measurement.
“Ambient” Temperature
The Ambient Temperature thermocouple port is used to make the Tamb
measurement. A Type K thermocouple must be used. The sensing tip of the thermocouple
should be located so that it receives air flow while the unit is sampling and is always shield
from the sun. By locating the sensor in this manner it can be used to monitor two items of
importance. Most importantly, this will allow for the accurate measurement of the ambient
temperature while the unit is sampling. In addition, when the unit is not sampling this allows
the temperature of the filter to be approximated. This can be of importance when sampling
for compounds that may changes phases (i.e. from solid to gas) due to changes in
temperature. Below, is a picture showing a suitable location for the thermocouple. Note the
thermocouple tip should be located so that it does not come into direct contact with any
surface.