Endress+Hauser Proline Promass 84 MODBUS RS485 Operating Instructions Manual page 105

Proline Promass 84 MODBUS RS485
Endress+Hauser
Calculation example (mass flow, liquids):
Given: Promass M / DN 25, measured value flow = 8000 kg/h
Max. measured error: ±0.10% ± [(Zero point stability ÷ measured value) · 100]% o.r.
Max. measured error: ±0.10% ± [(0.90 kg/h ÷ 8000 kg/h) · 100%] = ±0.111%
Repeatability
o.r. = of reading; 1 g/cc = 1 kg/l; T = medium temperature
• Mass flow (liquids):
±0.05% ± [½ · (Zero point stability ÷ measured value) · 100]% o.r.
• Mass flow (gases):
±0.25% ± [½ · (Zero point stability ÷ measured value) · 100]% o.r.
• Volume flow (liquids):
±0.10% ± [½ · (Zero point stability ÷ measured value) · 100]% o.r.
• Density (liquids): ±0.0005 g/cc
• Temperature: ±0.25 °C ± 0.0025 · T °C; (±0.5 °F ± 0.0015 · (T–32) °F)
Calculation example repeatability (mass flow, liquids):
Given: Promass M / DN 25, measured value flow = 8000 kg/h
Repeatability: ±0.05% ± [½ · (Zero point stability ÷ measured value) · 100]% o.r.
Repeatability: ±0.05% ± [½ · (0.90 kg/h ÷ 8000 kg/h) · 100%] = ±0.056%
Influence of medium temperature
When there is a difference between the temperature for zero point adjustment and the process
temperature, the typical measured error of the sensor is ±0.0002% of the full scale value / °C
(±0.0001% of the full scale value/°F).
Influence of medium pressure
The table below shows the effect on accuracy of mass flow due to a difference between calibration
pressure and process pressure.
DN
[mm] [inch]
8 3/8"
15 ½"
25 1"
40 1½"
50 2"
80 3"
o.r. = of reading
Promass M
[% o.r./bar]
0.009
0.008
0.009
0.005
no influence
no influence
Technical data
Promass M high-pressure version
[% o.r./bar]
0.006
0.005
0.003
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–
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