V
ELOCI
C
HECK
Operation
5
Measuring velocity
For highest accuracy, it is important with all
V
ELOCI
C
HECK
s to properly align the probe to the
flow. For accurate results, the measured air must
flow through the sensor window at the end of the
probe.
HINT for measuring velocity: If the probe is left to
warm up for more than a few seconds at
velocities below 50 feet/minute (0.25 meters/sec)
it will require more time to stabilize when it is
inserted into a higher flow. This is because the
probe assembly self heats at such low flows, and
must then re-stabilize when placed into higher
flow. Fro best response time at velocities of 100-
200 feet/minute (0.5-1 meters/sec) it is
recommended to first place the probe into the
flow, and then turn the meter on.
When the Model 8330 V
ELOCI
C
HECK
is in the
velocity mode the temperature sensor will be
warmed by heat from the velocity sensor. If the
V
ELOCI
C
HECK
is then switched to temperature
mode, it will read several degrees high until the
temperature sensor can cool. Therefore, when you
plan to measure both temperature and velocity, it is
best to measure temperature first.
