Siemens SITRANS P DS III - Page 205

Technical data
13.4 Measuring accuracy
SITRANS P DS III with PROFIBUS PA
Operating Instructions, 06/2013, A5E00053276-07
205
Differential pressure and flow rate measuring accuracy
HART
PROFIBUS PA and FOUNDATION
Fieldbus
• At -40 … -10°C and
+60 … +85°C
(-40 … 14°F and 140 … 185°F)
≤ (0.1 • r + 0.15) % per 10 K ≤ 0.25 % per 10 K
Effect of static pressure
• At the start of scale value
≤ (0.1 • r) % per 70 bar (1015 psi) ≤ 0.1% per 70 bar (1015 psi)
Measuring cell 20 mbar
(0.29 psi)
≤ (0.15 • r) % per 32 bar (464 psi) ≤ 0.15 % per 32 bar (464 psi)
• On the measuring span
≤ 0.15 % per 70 bar (1015 psi) -
Measuring cell 20 mbar
(0.29 psi)
≤ 0.2 % per 32 bar (464 psi) -
Effect of mounting position In pressure per change of angle
≤ 0.7 mbar (0.001015 psi) per 10° inclination
Correction via zero offset
Effect of auxiliary power supply In percent per change in voltage
0.005 % per 1 V
–
Measured value resolution
–
3 • 10
-5
of the rated measuring range
Level measuring accuracy
HART
PROFIBUS PA and FOUNDATION
Fieldbus
Reference conditions
• Rising characteristic curve
• Start of scale 0 bar
• Seal diaphragm stainless steel
• Measuring cell with silicone oil filling
• Room temperature 25 °C (77 °F)
• Measuring span ratio r
r = max. measuring span/set
measuring span
–
Measurement deviation with limit
setting, including hysteresis and
repeatability
Linear characteristic curve
≤ 0.075
• r ≤ 10
≤ 0.15% –
• 10 < r ≤ 30
≤ 0.3% –
• 30 < r ≤ 100
≤ (0.0075 • r + 0.075) % –
Settling time T
63
without electrical
damping
Approx. 0.2 s