Yokogawa digitalYEWFLO (DY) - Manual (Page 61)

MAINTENANCE
IM 1F2B4-01-YIA
Page 65
4.1.7 Activating Reynolds number correction
What is Reynolds Number Correction?
The YEWFLO vortex meter’s output is linear beginning at 20,000 Reynolds number, or 40,000 for sizes 6
inch and above. From 5,000 to 20,000 Reynolds number the meter’s output is nonlinear, but repeatable.
Reynolds number adjustment is a correction factor applied to the output to compensate for this non-
linearity within this Reynolds number range. When activated, flowmeter accuracy is improved to 0.8% of
rate throughout the flow range above 5000 Reynolds number. The correction factors listed below are
automatically applied when this feature is activated.
BT200 handheld terminal BT100 handheld terminal
D: adjust Select the D: adjust menu
and press e
nter .
Press Me
nu until the
D: Adjust menu appears.
D01: Reynolds adj
Active Scroll to the first parameter,
D01: Reynolds adj, press
enter . Depress the PRMTR key
and move to the first
parameter D01: Reynolds Adj.
Scroll to the active selection
and press e
nter twice.
Using INC or DEC select
active and press ent twice.
Press F4 {ESC} to return
to the parameter list.
D02: viscosity
1.0 Select parameter D02:
viscosity and press
enter . Press PRMTR to move to
D02: viscosity.
Input the flowing viscosity in centipoise
Press enter twice, Press f4
{esc } to return to the
parameter list.
Press e
nt twice.
D03 :Density F
8.3 Scroll to parameter
D03: DENSITY F and press
enter . Using the parameter key move
to the D03: DENSITY F
parameter.
Input the flowing density in units per B07.
Press ENTER twice.
Press e
nt twice.
The flowmeter will now be corrected for flowrates between 5,000 and 20,000 Reynolds number. Please be
sure to input accurate viscosity and density values, as this correction is only as valid as the accuracy of
these parameters. If viscosity and density change, accuracy will be affected until the new values are input.
Note: There are certain conditions where performance in the range of 5,000 to 20,000 Reynolds
number is not possible. Please consult the YEWFLO sizing program, your local representative or the
Yokogawa Industrial Automation factory for clarification.
Reynolds # 40,000 20,000 12,000 8,000 5,500
Correction 0% -1.0% -3.6% -6.5% -11.4%