Siemens SITRANS P500, Руководство по эксплуатации, Страница: 203 / 238

Technical data
11.4 Measuring accuracy
SITRANS P500 with HART
Operating Instructions, 12/2014, A5E02344528-09
203
Differential pressure and flow rate measuring accuracy
Influence of mounting position
In pressure per angular change
≤ 0.1 mbar (0.04 in H
2
O) per 10° inclination
Correction by zero offset
Power supply influence ≤ 0.005 % / 1 V
Measurement accuracy of level
Reference conditions
to IEC 60770-01
• Rising characteristic curve
•
Start of scale value 0 kPa/bar/psi
• Seal diaphragm stainless steel
•
Measuring cell with silicone oil filling
• Room temperature 25 °C (77 °F)
Measuring span ratio r (spread, Turn-Down) r = maximum measuring span/set measuring span
Conformity error at limit point setting, including
hysteresis and repeatability
•
Linear characteristic
r ≤ 10 r ≥ 10
25 kPa/250 mbar/100 inH
2
O
1.25 kPa/1250 mbar/502 inH
2
O
625 kPa/6250 mbar/2509 inH
2
O
≤ 0,03 % ≤ (0.003 • r) %
Long-term stability In 5 years ≤ 0.05 % • r %
In 10 years ≤ 0.08 % • r %
Influence of ambient temperature
1)
In percent per 28 °C (50 °F)
•
25 kPa/250 mbar/100 inH
2
O
≤ (0.025 • r + 0.014) %
• 1.25 kPa/1250 mbar/502 inH
2
O
•
625 kPa/6250 mbar/2509 inH
2
O
≤ (0.006 • r + 0.03) %
Effect of static pressure
•
At the start-of-scale value
25 kPa/250 mbar/100 inH
2
O ≤ (0.035 • r) % per 7 MPa/70 bar/1015 psi correc-
tion via zero point correction
1.25 kPa/1250 mbar/502 inH
2
O
625 kPa/6250 mbar/2509 inH
2
O
≤ (0.007 • r) % per 7 MPa/70 bar/1015 psi correc-
tion via zero point correction
•
On the span
25 kPa/250 mbar/100 inH
2
O
1.25 kPa/1250 mbar/502 inH
2
O
≤ 0.03 % per 7 MPa/70 bar/1015 psi
625 kPa/6250 mbar/2509 inH
2
O ≤ 0.09% per 7 MPa/70 bar/1015 psi
1)
Data only applies to the basic unit. The error of the remote seal must be considered as additive.