Fluid Components International RF83 Operation

CHAPTER 3 - OPERATION FLUID COMPONENTS INTL

3. Operation

Caution:

The control circuit contains electrostatic discharge (ESD) sensitive devices. Use standard ESD
precautions when handling the control circuit. See Chapter 2, Installation for ESD details.

Factory Calibrations

The RF83 Flow Switch is delivered in its standard factory set point form unless a custom factory calibration was
specified. The standard factory setting is mid-range between no flow and full flow. See Figures 3-1 and 3-2.

If the order included custom factory calibrations and alarm set points, keep all settings unchanged. The instrument is
ready for service without changes.

Field Calibrations for Flow Applications

If the factory calibrations were not ordered then follow one of the procedures below based on the particular
instrument purchased. If precise measurement is desired, FCI recommends that a FM71 Monitor/Calibrator be used.
Then the precise measurement of the signal voltage versus flow rate can be calculated for the alarm set points.

Alarm Set Point Adjustments By Observation or By Measurement

Alarm set points can be adjusted by observation or by precision measurements. The following procedure is
adjustment by observation. If adjustment by measurement is desired, obtain an FCI FM71 Calibrator/monitor and
follow the instructions found in the FM71 manual. For the highest accuracy,balancing the control circuit and creating
a calibration curve should be performed. These subjects are addressed later in this chapter.

Alarm A Set Point Procedure

1. Flow the pipeline at the desired flow direction and rate of flow.

2. Apply power to the instrument and allow 15 minutes for the sensing elements to become active and stabilize.

3. Locate the potentiometer (R5) and the red LED on the control circuit. (See Figure 3-3 or 3-4.)

4. Choose A or B.
A. Detecting No Flow or Decreasing Flow Rate

If the LED is off, turn the potentiometer clockwise until the LED turns on. If the LED is on, turn the potentiometer
counterclockwise until the LED turns off, then turn the potentiometer clockwise until the LED just turns on. With the
LED on, turn the potentiometer slowly counterclockwise until the LED just turns off. Turn the potentiometer one­half turn past the point at which the LED just turns off. Be aware that the potentiometer may have up to one quarter
turn of hysteresis. If the mark is overshot, the procedure should be repeated. See Figures 3-1and 3-2 for
potentiometer position and curve results.

B. Detecting Maximum Flow or Increasing Flow Rate

If the LED is on, turn the potentiometer counterclockwise until the LED turns off. If the LED is off, turn the
potentiometer clockwise until the LED turns on, then turn the potentiometer counter clockwise until the LED just
turns off. With the LED off, turn the potentiometer slowly, clockwise until the LED just turns on. Turn the
potentiometer one-half turn past the point at which the LED just turns on. Be aware that the potentiometer may have
up to one quarter turn of hysteresis. If the mark is overshot, the procedure should be repeated. See Figures 3-1 and
3-2 for potentiometer position and curve results.

Doc. No. 003147 Rev. B 3 - 1

Model RF83 Flow Switch

FLUID COMPONENTS INTL CHAPTER 3 - OPERATION

Figure 3-1. Setting Forward and Reverse Alarm Switch Points

Figure 3-2. Control Circuit Outline Drawing

Model RF83 Flow Switch 3 - 2 Doc. No. 003147 Rev. B