Model PD690 Universal Process Meter
Instruction Manual
24
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Select Square Root Extraction (
L or S
)
With the square root extraction function activated, the meter takes the
square root of the input signal (the output from a differential pressure
transmitter) and displays flow rate. The square root extraction feature
is calibrated using the same
S
ingle
B
utton
S
caling technique that is
used for two-point linear calibration. Calibration involves setting only
three points: the zero flow rate (usually zero), the high flow rate and
the Low-Flow Cutoff point.
To program the meter for square root extraction, push
ENTER
. When
(
L or S
) appears, push
ENTER
again. The meter will flash (
L or S
)
alternately. Push
ENTER
when (
S
) is flashing. After (
S
) has been
selected the meter will switch to indication mode and is ready to be
calibrated.
Program Low-Flow Cutoff (
[utoFF
)
Low-Flow Cutoff allows the meter to be programmed so that the often
unsteady output from a differential pressure transmitter at Low-Flow
rates always displays zero on the meter.
Example: If Low-Flow Cutoff is set at 12, any rate less than 12 will be
displayed as "0".
To program Low-Flow Cutoff:
1. Push
ENTER
, when
[vtoFF
appears push
ENTER
again.
2. Set Low-Flow Cutoff per
Five Basic Digit/Display-setting
Instructions on page 19.
Notes:
1. To disable Low-Flow Cutoff, program cutoff value to zero.
2. Low-Flow Cutoff is only available when using Square Root
Extraction.
