CALIBRATION
From
CALIBRATION
press
È
to
Pipe ID
and
Æ
to place the cursor under the digits and
È
or
Ç
to
change the numbers and decimal point. Pipe ID should be entered as the exact inside diameter of the
pipe where the sensor is mounted.
Press
Æ
to return the cursor to
Pipe ID
and
È
to
MaxF.
Set digits to the maximum flow rate in your
application. If maximum flow is unknown, enter an estimated maximum and observe actual flow to
determine the correct maximum value. (
MaxF
entry is required
only
to set 20mA output at a specific
flow rate and maximum flow in the optional data logger.
MaxF
setting has no effect on the DFM-IV
digital display, totalizer, or control relays).
4-20mA CURRENT LOOP
Some applications may require the 4-20mA output to be offset so that 4mA or 20mA correspond to flow
rates other than Zero and Maximum.
4
mA at
use
È
or
Ç
to set % output for 4mA. It is adjustable from -5% (3.8mA) up to
15% lower than the 20mA setting. Adjustment resolution is 0.05% (0.01mA).
2
0mA at
use
È
or
Ç
to set % output for 20mA (down to 15% greater than the 4mA
setting and up to 300%). Adjustment resolution is 0.05% (0.01mA).
DAMPING
Increase damping to stabilize readings under turbulent flow conditions. Damping time shown in
percentage is the interval for a zero to full scale display change (maximum 99 percent). Factory default
is 20 percent.
DFM-IV Doppler Flow Meter
Manual Series A.6
Page 8
UNITS / MODE
RELAY PARAMETERS
Pipe ID 1.000 ft
MaxF 10.00 ft3/s
4mA @
0.00 %
20mA @
100.0 %
*** STORING ***
CALIBRATION
Damping
10
%
Store?
Yes
