Micronics U3000 User Manual

3: Operating Procedures
U3000/U4000 User Manual 25
(Issue 2.0)
3. Connect a calibrated ammeter to the 4-
20mA output and adjust the UP/DOWN
Scroll keys (Coarse) and LEFT/RIGHT
Scroll keys 5 & 6 (fine) until the output is
exactly 4.00mA.
The DAC should indicate approximately
8000.
4. Press ENTER when done.
5. With the meter still connected to the 4-
20mA output adjust the Scroll keys to
obtain an output of exactly 20.00mA.
The DAC should indicate approximately
40000.
6. Press ENTER when done.
4-20mA Signal scaling
Note: The 4-20mA can be set to represent a particular flow range. It is also possible to enter a negative figure
for the minimum output and this would enable a reverse flow to be monitored.
7. With the instrument operating in the FLOW
READING mode, press the 4-20mA function
key. This will access the 4-20mA OUTPUT
screen.
8. Select Flow at max. output and press
ENTER, then enter a value of the flow
rate that you want to associate with a
20.00mA output.
9. Select Flow at min. output and press
ENTER then enter a value of the flow rate
that you want to associate with a 4.00mA
output. This could be ‘0’.
10. Select Output mA for error and enter a value (max of about 26mA) that you want the 4-20mA
output to produce in the event of an error (e.g. if the flow-rate is outside the set range).
11. Upon completion press ENTER to return to the FLOW READING screen.
How to convert the measured current to flow rate
Assume the maximum flow rate is F
max
(l/min) and the minimum flow rate F
min
is ‘0’ (l/min), as shown.
CALIBRATE 4mA DD-MM-YY HH:MM:SS
Dim: mm
Adjust the output current to 4mA
Use
UV to set, 5/6 to trim
DAC Value: 8000
Press
 when done
CALIBRATE 20mA DD-MM-YY HH:MM:SS
Dim: mm
Adjust the output current to 20mA
Use
UV to set, 5/6 to trim
DAC Value: 40000
Press
 when done
4-20 mA OUTPUT DD-MM-YY HH:MM:SS
4-20 mA O/P is ON Dim: mm
mA Output Reading : 0.00
Output Range : 4-20
Units : l/min
Flow at max. output : 0.00
Flow at min. output : 0.00
Output mA for error : 22.00
Exit
4 8 12 16 20
F
max
Flow (l/min)
I (mA)
F
min
[0-16mA scale]
[0-20mA scale]
[4-20mA scale]

Micronics U3000 Specifications

General

Brand	Micronics
Model	U3000
Category	Measuring Instruments
Language	English