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Turbine Flow Meter Manual 05/13 - 0721-1 / 13518 Page 28
5.2.2 Procedure
1. Determine the input frequency required to simulate the desired maximum ow rate using the
equation below:
2. Remove the ow meter from the pipe and make sure the electrode and the surrounding area
are dry.
3. Choose the input frequency range (Hz) from the table on the next page and set the appropriate
range selection jumper. Refer to Appendix A for the internal wiring diagram of your model.
4. Connect the pulse generator output lead to the test signal input lead on the analog card, and
connect the pulse generator ground lead to the black ground wire in the ow meter cable. Set
the output to a 15 V P-P square wave at the frequency determined in step #1.
5. Set the DC voltmeter to the 0-10 V scale and connect the (+) lead to the brown wire in the ow
meter cable. Connect the (-) lead from the voltmeter to the black ground wire in the ow meter
cable.
6. Connect the red and black wires in the ow meter cable to the (+) and (-) terminals of the 24 V
power supply respectively. Apply power.
7. Adjust the span potentiometer on the analog card to produce a 10 V reading on the voltmeter.
NOTE: The frequency ranges in the table below are a starting point, and since they vary with
electronic component tolerance, it may be necessary to change the jumper position once rescaling
is started. If the range of adjustment of the span potentiometer is not sufcient to produce the
desired 10 VDC, change the jumper position as follows:
VOLTAGE READING TOO HIGH: Choose the next lower jumper position.
VOLTAGE READING TOO LOW: Choose the next higher jumper position.
8. The ow meter is now rescaled. Disconnect all equipment, replace the cover and reinstall the
ow meter.
Where:
F = Input Frequency (Hz)
R = Maximum Flow Rate
MF = Meter Factor*
*The meter factor is written on a calibration tag attached to each meter and is also
recorded on the calibration data sheet. Use one of the three formulas provided based
on the engineering units for the meter factor. Please contact ONICON if you cannot
locate the meter factor, or if you wish to use the meter in a different pipe size.
For GPM For l/s For M3/hr
MF in pulses per gallon (ppg) MF in pulses per liter (ppl) MF in pulses per meter3 (ppm3)
F = R x MF
60
F = R x MF F = R x MF
3600
Analog Range Jumper Settings
INPUT FREQUENCY (Hz) SWITCH POSITION
AT MAXIMUM FLOW RATE SINGLE/DUAL TURBINE
Over 248 Hz 1
124 – 248 Hz 2
62 – 123 Hz 3
31 – 61 Hz 4
15 – 30 Hz 5
Under 15 Hz 6