V
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Operation
7
Selecting the sensor response
The Model 8330 V
ELOCI
C
HECK
has a
FAST/SLOW
response switch for setting the
sensor response speed. In the slow response mode,
the V
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C
HECK
displays the average velocity
measured during the past 12 seconds. This is a
running average, so the display is updated once a
second. In the fast response mode, the meter
displays the average velocity measured during the
past 3 seconds. The way the V
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HECK
does
velocity averaging is by saving the velocity
measured each of the past 12 seconds into 12
separate locations in memory. Every second, a new
reading is taken and the oldest reading is thrown
out. Depending on the position of the sensor
response switch, either the last 3 readings or all 12
readings will be averaged for display.
Batteries
The V
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C
HECK
is powered by four AA-size
batteries. TSI ships the instrument with alkaline
batteries, but nickel-cadmium rechargeable
batteries may be used. Keep in mind that battery
life is a function of the velocity being measured:
the higher the velocity, the shorter the life. Table 2
shows typical battery life for both alkaline and
nickel-cadmium batteries at three velocities.
