User Manual

42
Signet 8900 Multi-Parameter
Custom point #10
3000 gal.
Custom point #1
0 gal.
Custom point #2
45 gal.
Custom point #3
118 gal.
Custom point #4
Custom point #5
250 gal.
Custom point #9
1300 gal.
Custom point #6
380 gal.
Custom point #7
700 gal.
Custom point #8
1000 gal.
160 gal.
Level and Volume conversion in custom shaped vessels
If you select Custom Shape in the Options menu, you can de ne
from 2 to 20 Custom Points to establish the relationship of level to
volume in the vessel.
Select Manual level Measurement mode to edit both level and
volume data (dry con guration).
Select Automatic level Measurement mode to accept the
sensor measurement of the Level, while you assign a
volumetric value to each custom point (wet con guration).
Enter from 2 to 20 custom points to link level and volume
values.
• The rst custom point must be the lowest uid level in the
vessel.
Each successive point must be greater than the preceding
point.
The last point must be equal to or greater than the highest
uid level in the vessel.
A custom point should be located at all transition points in
the vessel shape (for example, at custom point #9, where the
shape changes from a cylinder to a cone).
The more complex sections should be de ned with more
points. Notice that the conical section of the illustration has
been de ned by custom points 1 through 9.
Simpler sections require fewer de ning points. Note that the
cylinder requires only custom points 9 and 10.
Level, volume and mass calculations performed by the 8900
include:
Pressure to level conversion:
Level = P ÷ (SG • D
(water)
)
where P = Pressure
SG = Speci c Gravity of uid
D
(water)
= Density of water
With pressure in psi: Level (meters) = (0.703069 • P / SG)
with pressure in bar: Level (meters) = 1.019715 • P / SG)
Mass conversion
m = D
(water)
• SG • V
where m = mass of uid
D
(water)
= Density of water = 1000 kg/m
3
SG = Speci c Gravity of uid
V = Volume of uid (m
3
)
m (kg) = 1000 • SG • V
r
h
Length
A
Technical Reference for Level measurement
Volume calculations
Vertical cylinder: V = • d
2
• h/4
where d = diameter of cylinder
h = height of uid
Rectangular vessel: V = w • l • h
where w = width
l = length
h = height
Horizontal cylinder: V = A • L
where A = area of segment
L = Length of vessel
r = radius of vessel
h = height of segment
Custom vessel:
The 8900 performs linear interpolation between adjacent points.