Measuring Accuracy Of Sitrans P320; Reference Conditions; Effect Of Auxiliary Power Supply; Gauge Pressure - Siemens SITRANS P Operating Instructions Manual

Technical data

13.2 Measuring accuracy of SITRANS P320

For devices with functional safety, the minimum permissible measuring span is limited by the
1)
spread. Therefore, ensure that the configured spread is no higher than 5:1.
Level measuring limits
Lower measuring limit
Measuring cell with silicone oil
filling
Measuring cell with inert oil
Measuring cell with FDA-com‐
pliant oil
Upper measuring limit
Lower range value
13.2 Measuring accuracy of SITRANS P320
13.2.1

Reference conditions

● According to EN 60770-1/IEC 61298-1
● Rising characteristic curve
● Lower range value 0 bar/kPa/psi
● Seal diaphragm stainless steel
● Measuring cell with silicone oil filling
● Room temperature 25 °C (77 °F)
13.2.2

Effect of auxiliary power supply

0.005% per 1 V (in percent per change in voltage)
13.2.3

Gauge pressure

Conformity error at limit point setting, including hysteresis and repeatability - gauge pressure
Measuring span ratio r (spread, Turn-Down)
● Linear characteristic curve
● Linear characteristic curve
208
-100% of max. measuring range or 30 mbar a/3 kPa a/0.44 psi a depending
on the mounting flange
-100% of max. measuring range or 30 mbar a/3 kPa a/0.44 psi a depending
on the mounting flange
-100% of maximum measuring range or 100 mbar a /10 kPa a /1.45 psi a
100% of max. range
Between the measuring limits (continuously adjustable)
250 mbar/25 kPa/3.6 psi
r = max. measuring span/set measuring span and nominal
measuring range
r ≤ 1.25
≤ 0.075%
r ≤ 5
SITRANS P320/P420 with 4 to 20 mA/HART
Operating Instructions, 11/2019, A5E44852162-AC
1.25 < r ≤ 30
≤ (0.008 • r + 0.055)%
5 < r ≤ 100