TSI Instruments AccuBalance 8370, Operation And Service Manual

Page: 36 / 58

28 Chapter 2
In the averaging mode, the A
CCU
B
ALANCE
takes flow measurements
for three or six seconds and then displays and holds the time-averaged
flow. The averaging time can be changed between three and six
seconds by changing DIP switch 6 inside the battery compartment (see
Changing DIP Switch Settings later in this chapter). The display will
count down while the A
CCU
B
ALANCE
is taking flow measurements.
Notice : You must keep the A
CCU
B
ALANCE
in place during the
entire countdown and until the time-averaged
measurement appears on the display.
Selecting Flow Units
The A
CCU
B
ALANCE
is capable of displaying measured flow rates in
three different measurement units: CFM (Cubic Feet per Minute), l/s
(Liters per Second), and m3/hr (Meters cubed per Hour). DIP
switches 3 and 4 control the display units. Refer to
Changing DIP
Switch Settings later in this chapter to change the flow units.
Selecting the Time Constant
The A
CCU
B
ALANCE
allows you to choose between two measurement
speeds in both the continuous reading mode and in the averaging
mode. In the continuous reading mode you may select either a one-
second or a two-second display update rate. The A
CCU
B
ALANCE
is
shipped from the factory set up to operate at the one-second display
rate. You may change to a two-second display rate by adjusting
switch 7 under the battery cover (see
Changing DIP Switch Settings ).
The flow sensor in the A
CCU
B
ALANCE
is extremely fast and actually
samples flow at a rate of 10 times per second. Thus, the values
displayed in the one-second mode represent an integration of 10
readings each. Likewise, the values displayed in the 2-second mode
represent an integration of 20 readings each. By selecting the slower