Dwyer 641RM - Manual (Page 3)

Two buttons and a potentiometer control the setup process.
The SELECT button is used to scroll between the setup
parameters.
The ENTER button allows access to each parameter for
adjustment.
The ADJUST potentiometer is used to change the value of
the parameters.
Holding the ENTER button for 2.5 seconds saves the new
parameter value.
Making Adjustments
The adjustment process has three steps: select the para-
meter, adjust the parameter, save the new value. These are
described in the following steps.
1. Select the parameter: Each time the SELECT but-
ton is pressed the LED indicator will advance to the next
parameter. When the last parameter, SPAN, is selected,
the next time the SELECT is pressed the unit will return
to RUN mode. Press the SELECT button until the LED
indicator illuminates the desired parameter. Press
ENTER. The selected indicator will begin to blink, show-
ing the parameter may now be adjusted. If the unit is left
in the setup mode, after several minutes it will reset to
the operate mode.
2. Adjust the parameter: Turn the ADJUST poten-
tiometer until the desired setting is made. This may be
adjusted using a small screwdriver or similar tool. Be
careful not to force the control past its stops or damage
will result.
3. Save the parameter: To save the new parameter
press and hold the ENTER button. The LED indicator will
begin to flash at a faster rate. After about 2.5 seconds
all of the LED indicators will flash when the parameter is
saved. If you do not want to save the parameter press
the SELECT button without entering the parameter. The
adjusted value will be discarded and next LED indicator
will be illuminated.
Adjusting the Output Filter
The output filter may be adjusted to smooth the readings
when measuring turbulent flow. The time constant may be
adjusted from 0.5 seconds to 15 seconds. To adjust the fil-
ter time constant, select the FILTER indicator. Press ENTER
to enable adjustment. Turn the ADJUST until the desired
amount of damping is achieved. To save the value press and
hold the ENTER button until the LED indicators all flash, indi-
cating the value was saved. To discard the adjustment press
SELECT before pressing the ENTER button.
Range Selection
The range selection allows you to select one of eight ranges
in either feet per minute (FPM) or meters per second (MPS).
Ranges:
FPM: 250, 500, 1000, 2000, 3000, 5000, 10000, 15000
MPS: 1.25, 2.5, 5, 10, 15, 25, 50, 75
Select the RANGE indicator by pressing ENTER when the
RANGE LED indicator is illuminated. The A,B,C LED indi-
cators will display which range setting is currently active.
Press ENTER to enable adjustment. Turn the ADJUST until
the desired range indication is achieved. If you want to dis-
card the adjustment press SELECT. If you want to save the
range press and hold ENTER. The RANGE LED will blink at
a faster rate for about 2.5 seconds then all of the LEDs will
flash indicating the value was saved.
The range setting is displayed with the LED indicators. The
function of these indicators is summarized on the control
label inside the unit. The following table summarizes the
indicator status for each range setting
1: Indicator on
0: Indicator off
% of Full Velocity
63%
90%
95%
99%
Min.
0.5
1.1
1.5
2.3
Mid.
7.5
17.3
22.5
34.5
Max.
15
34.5
44.9
69.0
Range/Units
250 FPM
500 FPM
1000 FPM
2000 FPM
3000 FPM
5000 FPM
10000 FPM
15000 FPM
1.25 MPS
2.5 MPS
5 MPS
10 MPS
15 MPS
25 MPS
50 MPS
75 MPS
Run
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
Filter
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
Range
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
Span
A
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
4 mA
B
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
20 mA
C
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
OUTPUT FILTER RESPONSE (values in seconds)
Page 3
Filter Setting on Adjust Dial
641-RM bulletin 2/1/05 11:53 AM Page 3