Dwyer UFB - Manual (Page 29)

3: Operating Procedures
25
3.4 Outputs
The UFB has configurable Current, Pulse, and Alarm outputs.
3.4.1 Current output
Note: Where long cable runs are necessary, or noise pickup is causing unstable flow readings, the use of two
core screened cable such as BELDEN 9501 060U500, or similar, is recommended for use with the 4 to 20 mA
current output. The cable screen should be connected to the RS232 GND terminal.
How to turn the 4 to 20 mA output OFF/ON
1. With the instrument operating in the FLOW
READING mode, press the 4-20mA function
key. This will access the
4-20mA OUTPUT
screen.
2. The ON/OFF status of the 4-20mA output is
shown on line 2 of the display.
3. To change the ON/OFF status select Output
Range and press ENTER
4. Select Off, to turn OFF the 4-20mA Output or
select one of the output ranges to turn it ON.
5. Press ENTER to return to the 4-20mA OUTPUT
screen
4 to 20 mA Signal calibration and ranging
This procedure describes how to calibrate the 4 to 20 mA output and ‘scale’ it to cover a defined flow-rate range.
Signal calibration
6. Select Setup Instrument from the MAIN
MENU then press ENTER to access the SETUP
INSTRUMENT screen.
7. Select Calibrate 4-20mA. and press ENTER
Key Point: The 4 to 20 mA output has been calibrated in the factory and should not
require further adjustment. In the rare event that re-calibration is necessary, this
procedure should be carried out only by a trained engineer.
4-20 mA OUTPUT * *
4-20 mA O/P is ON
mA Output Reading : 0.00
Output Range : 4-20
Units : gal/min
Flow at max. output : 0.00
Flow at min. output : 0.00
Output mA for error : 22.00
Exit
4-20 mA OUTPUT * *
Off
4-20mA
0-20mA
0-16mA
SETUP INSTRUMENT * *
Set Date & Time : dd-mm-yy hh:mm:ss
Calibrate 4-20mA
Factory settings
Change Language
Exit