Description of device parameters Proline Promag 300 Modbus RS485
86 Endress+Hauser
Additional information Dependency
The unit is taken from the Density unit parameter (→ 60)
Ref. temperature
Navigation Expert → Sensor → External comp. → Ref. temperature (1816)
Prerequisite The Fixed density option or External density option are selected in the Density source
parameter (→ 85).
Description Use this function to enter a reference temperature for calculating the reference density.
User interface –273.15 to 99 999 °C
Factory setting Country-specific:
• +20 °C
• +68 °F
Additional information Dependency
The unit is taken from the Temperature unit parameter (→ 58)
Reference density calculation
ρ
n
ρ α β(1 + + ⋅∆t⋅ ⋅∆t )
2
=
A0023403
• ρ
N
: reference density
• ρ: fluid density currently measured
• t: fluid temperature currently measured
• t
N
: reference temperature at which the reference density is calculated (e.g. 20 °C)
• ∆t: t - t
N
• α: linear expansion coefficient of the fluid, unit = [1/K]; K = Kelvin
• β: square expansion coefficient of the fluid, unit = [1/K
2
]
Ref. density
Navigation Expert → Sensor → External comp. → Ref. density (1892)
Prerequisite The Calculated value option is selected in the Density source parameter (→ 85)
parameter.
Description Displays the reference density.
User interface Positive floating-point number