LI-COR LI7200RS, Instruction Manual

Page: 73 / 226

Configuring the Flow Module
The 7200-101 Flow Module is configured through the LI-7200 Windows software
from
LI-7200 > Flow Module
. See the 7200-101 Instruction Manual for more
information.
The window displays the following variables:
l
Measured flow (SLPM): Standard Liters per Minute, mass flow.
l
Measured flow (LPM): Liters per Minute; volumetric flow corrected for tem-
perature and pressure.
l
Pressure drop (kPa): This value indicates the pressure drop resulting from
tubing, filters, the sensor head, or obstructions in the filter/tubing. The range is
from 0 to 4.5 kPa, with a normal reading near 1.0. This value will rise if the fil-
ter becomes clogged, indicating that the filter should be serviced.
l
Motor drive (%): Percent of Pulse Width Modulation (PWM) drive input to the
blower motor. This value will be near 25% when the flow plumbing is carefully
installed. The value will increase if there are a lot of bends in the hose, or if the
filter becomes clogged. An increase in the motor drive percentage indicates that
the flow path is restricted and may need service.
Section 3. Operation
3-31 Configuring the Flow Module