Endress+Hauser Proline Promass E 500 - Page 276

Technical data Proline Promass E 500 PROFIBUS PA
276 Endress+Hauser
Influence of medium
pressure
The following shows how the process pressure (gauge pressure) affects the accuracy of the
mass flow.
o.r. = of reading
It is possible to compensate for the effect by:
• Reading in the current pressure measured value via the current input or a digital
input.
• Specifying a fixed value for the pressure in the device parameters.
Operating Instructions .
DN [% o.r./bar] [% o.r./psi]
[mm] [in]
8 ³⁄₈ no influence
15 ½ no influence
25 1 no influence
40 1½ no influence
50 2 –0.009 –0.0006
80 3 –0.020 –0.0014
Design fundamentals o.r. = of reading, o.f.s. = of full scale value
BaseAccu = base accuracy in % o.r., BaseRepeat = base repeatability in % o.r.
MeasValue = measured value; ZeroPoint = zero point stability
Calculation of the maximum measured error as a function of the flow rate
Flow rate Maximum measured error in % o.r.
ZeroPoint
BaseAccu
⋅ 100
³
A0021332
± BaseAccu
A0021339
ZeroPoint
BaseAccu
⋅ 100
<
A0021333
ZeroPoint
MeasValue
⋅ 100
±
A0021334
Calculation of the maximum repeatability as a function of the flow rate
Flow rate Maximum repeatability in % o.r.
½ ⋅ ZeroPoint
BaseRepeat
⋅ 100
³
A0021335
A0021340
½ ⋅ ZeroPoint
BaseRepeat
⋅ 100
<
A0021336
ZeroPoint
MeasValue
⋅ 100
½ ⋅±
A0021337