8.2.4 Gauge pressure from the differential pressure series
Conformity error at limit point setting, including hysteresis and repeatability - gauge pressure from the differential pressure
series
Measuring span ratio r (spread, Turn-Down) r = max. measuring span/set measuring span and
nominal measuring range
● Linear characteristic curve
r ≤ 5 5 < r ≤ 20
20 mbar/2 kPa/8.031 inH
2
O ≤ 0.075% ≤ (0.005 • r + 0.05)%
● Linear characteristic curve
r ≤ 5 5 < r ≤ 60
60 mbar/6 kPa/24.09 inH
2
O ≤ 0.075% ≤ (0.005 • r + 0.05)%
● Linear characteristic curve
r ≤ 5 5 < r ≤ 100
250 mbar/25 kPa/3.6 psi
600 mbar/60 kPa/240.9 inH
2
O
1600 mbar/160 kPa/642.4 inH
2
O
5000 mbar/500 kPa/2008 inH
2
O
30 bar/3 MPa/435 psi
≤ 0.065% ≤ (0.004 • r + 0.045)%
● Linear characteristic curve
100 bar/10 MPa/1450.3 psi r ≤ 10 10 < r ≤ 30
≤ 0.1% ≤ 0.2%
Effect of ambient temperature - gauge pressure from differential pressure series
In percent per 28 °C (50 °F)
20 mbar/2 kPa/8.031 inH
2
O ≤ (0.15 • r + 0.1)%
60 mbar/6 kPa/24.09 inH
2
O ≤ (0.075 • r + 0.1)%
250 mbar/25 kPa/3.6 psi
600 mbar/60 kPa/240.9 inH
2
O
1600 mbar/160 kPa/642.4 inH
2
O
5000 mbar/500 kPa/2008 inH
2
O
30 bar/3 MPa/435 psi
≤ (0.025 • r + 0.125)%
100 bar/10 MPa/1450.3 psi ≤ (0.08 • r + 0.16)
Long-term stability at ±30 °C (±54 °F) - gauge pressure from differential pressure series
20 mbar/2 kPa/8.031 inH
2
O Per year ≤ (0.2 • r)%
60 mbar/6 kPa/24.09 inH
2
O In 5 years ≤ (0.25 • r)%
250 mbar/25 kPa/3.6 psi
600 mbar/60 kPa/240.9 inH
2
O
1600 mbar/160 kPa/642.4 inH
2
O
5000 mbar/500 kPa/2008 inH
2
O
In 5 years ≤ (0.125 • r)%
In 10 years ≤ (0.15 • r)%
30 bar/3 MPa/435 psi In 5 years ≤ (0.25 • r)%
In 10 years ≤ (0.35 • r)%
100 bar/10 MPa/1450.3 psi In 5 years ≤ (0.25 • r)%
Technical data
8.2 Measuring accuracy of SITRANS P320
SITRANS P320/P420 with 4 to 20 mA/HART
Compact Operating Instructions, 09/2018, A5E38874562-AB 71