Advanced features, Flow rate correction equation – Fluid Components International GF90_GF92 User Manual
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Doc. No. 06EN003229 Rev. H
41
GF Series Flow Meter Models GF90/GF92
FLUID COMPONENTS INTERNATIONAL LLC
http://www.fluidcomponents.com
To view the relay switching parameters:
1.
From the Main menu press 5. The 5.0 VERIFY menu title will appear.
2.
Press 7, the Relay option. The two screens in Figure 26 describe how the two relays will react
to changes in flow rate or temperature. Screen 1, line 1 is the current status of relay 1. Line 2
shows that the relay will change states when the flow rate exceeds 100 SCFM. The last line
displays a hysteresis (H) of 5 SCFM and a delay of about 3 seconds. Screen 2, line 1 is the
current status of relay 2. Line 2 and 3 shows that the relay will switch states on changes in
temperature (°F). The state of the relay will change when the temperature is inside the
temperature range of -50 to 150 °F. The last line displays a hysteresis (H) of 2 °F and a delay of
about 1 second.
RELAY 1: OFF
Above 100 SCFM
H: 5.00 D: 3.00
RELAY 2: ON
°F (Inside)
-50 to 150
H: 2.00 D: 1.00
Window 1
Window 2
C00246-1
Figure 26. Relay Status Verification Display
The remainder of this chapter contains topics that may not be applicable to every user of the flowmeter.
In most cases the flowmeter will be ready for use straight out of the box. However, there may be an
application where the advanced features of the flowmeter may be needed. This section discusses how
to correct for bias errors due to non-ideal installations, how to communicate with the flowmeter through
the serial port, and how to use the multiple calibration options.
Flow Rate Correction Equation
The flow rate correction equation or corrector is used to bias the flow rate output. The correction
equation contained in the flowmeter allows the user to correct for bias errors due to non-ideal
installation effects. The correction equation is applied to the measured flow rate and then this corrected
flow rate is used to drive the analog outputs and manipulate the relays. The flow rate shown on the
display is also the corrected value. Figure 27 describes how the correction equation is applied.
The correction equation for the flowmeter is shown below.
mnew = F1 + (F2 x mo )+ (F3 x mo2 )+( F4 x mo3)
where
mo = Measured Flow Rate
Fi = Correction Equation Coefficients ( i = 1 through 4 )
mnew = Corrected Flow Rate
Advanced
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