Endress+Hauser Proservo NMS83 Operating Instructions Manual page 105

Proservo NMS83
Endress+Hauser
Thermal tank shell correction (CTSh)
CTSh (correction of the thermal tank shell expansion) compensates for effects on the
Gauge Reference Height (GRH) due to temperature effects on the tank shell or stilling well.
The temperature effects are separated into two parts, respectively effecting the ' d ry' and
' w etted' part of the tank shell or stilling well. The calculation is based on thermal expansion
coefficients of steel and insulation factors for both the ' d ry' and ' w et' shell. The assessed
temperatures are based on manual or measured values and the temperature of the shell
when the tank was calibrated (for details refer to API MPMS Chapter 12.1).
This correction is recommended for the following situations:
• if the operating temperature deviates considerably from the temperature during
calibration (ΔT > 10 °C (18 °F))
• for extremely high tanks
• for refrigerated, cryogenic or heated applications
As the use of this correction will influence the innage level reading, it is
recommended to review the manual hand dip and level verification procedures prior
to enabling this correction method.
The thermal tank shell correction (CTSh) is configured in the CTSh submenu
(→  258).
Commissioning
105