Endress+Hauser Proline Promag 300, Описание параметров устройства

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Proline Promag 300 Modbus RS485 Description of device parameters
Hauser 87
Additional information Description
The reference density is required for density calculation.
Deviation of the process temperature from the reference temperature:
∆T = T - T
ref
∆T: Deviation
T: Process temperature
T
ref
: Ref. temperature (→  86)
Temperature-compensated density:
ρ
comp
= ρ
ref
(1 + α∆T + β∆T 2 )
ρ
comp
: Calculated density
ρ
ref
: Reference density
∆T: Deviation of the process temperature from the reference temperature
α: Linear exp coeff (→  88)
β: Square exp coeff (→  88)
Example for water (factory setting)
For a reference temperature of T
ref
= 20 °C
A quadratic fit of a number of density values results in the following coefficients:
• α = –2.0295 · 10 -4 1/K
• β = –3.8436 · 10 -6 1/K 2
• ρ
ref
= 997.82 kg/m 3
1010
1000
990
980
970
960
Dichte [kg/m ] ³
0 -20 40 20 60 80
A0031441
 2 Quadratic fit
Dependency
The unit is taken from the Density unit parameter (→  60)