Azbil JTD910S - Page 108

3-42
Chapter 3 Starting and Stopping this Device
0% liquid level differential pressure
Lower range value (LRV) = h×ρ+d×ρ
0
100% liquid level differential pressure
Upper range value (URV) = l×ρ+ h×ρ+ d×ρ
0
= (l+h)×ρ+d×ρ
0
Accordingly,
Low limit (LRV): hρ+d×ρ
0
High limit (URV): (l+h)ρ+dρ
0
is the range to set.
Calculation example:
ρ: 0.9
ρ
0
: 1.0
l: 1500 mm
h: 250 mm
d: 500 mm
would result in:
0% liquid level differential pressure
LRV = 250×0.9+500×1.0 = 725 mm H
2
O = 7.110 kPa
100% liquid level differential pressure
URV = {(1500+250)×0.9}+500×1.0 = 2075 mm H
2
O = 20.35 kPa
Accordingly,
Low limit (LRV): 7.110 kPa
High limit (URV): 20.35 kPa
is the resulting range.