Endress+Hauser Proline Promag 300 - Page 87

Proline Promag 300 Modbus RS485 Description of device parameters
Endress+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 4020 60 80
A0031441
 2 Quadratic fit
Dependency
The unit is taken from the Density unit parameter (→  60)