Kobold Heinrichs Coriolis, Руководство по эксплуатации

Страница: 94 / 105

Page 94 of 105 OPERATING MANUAL HPC & UMC4
15. Density calibration
For continuous processes, which process only small variations in temperature and liquid media of compa-
rable density, a density calibration can be carried out locally.
15.1 Conditions
For a local density calibration the following conditions must be fulfilled:

The sensor must be suitable for a density measurement. For all these sensors the manufacturer
offers a 3-point calibration with an accuracy of at least 5 g/l. Sensors, for which the manufacturer
calibration is not offered, are also not suitable for local single point calibration.

For the local calibration the medium’s density must be known or be determined by a suitable pro-
cedure using exactly the same process temperature present in the sensor during measurement.

The medium must be liquid. The one-point density calibration is not suitable for gaseous media.
15.2 Procedure
The procedure of the density calibration is as follows:

First the transmitter is switched on and the sensor is filled with the medium under operating con-
ditions.

So that the sensor including housings and flanges can take the operating temperature a waiting
period of at least 15 minutes is to be kept.

After the input of the customer’s password select functional class DENSITY and “density calibra-
tion hot medium
”. (See also chapter 14.6.15 on page 68.)

Independently of the kind of the liquid medium and its temperature the beginning of the calibra-
tion is confirmed by selecting “yes”. Thereupon the transmitter measures medium temperature
and current resonant frequency of the sensor.

In the following the function “measured values hot medium“ has to be selected The displayed
measured values of temperature and frequency are confirmed by 2 times pressing the Enter-key.
In the next field the density of the medium has to be entered in unit of g/l or kg/m³. (See also
chapter 14.6.16 on page 68.)

Subsequently, the function “finish density calibration” is used to finish density calibration. (See al-
so chapter 14.6.17 on page 68.)

Finally the function “density measurement on/off” activates the density measurement. (See also
chapter 14.6.1 on page 64.)

Now the measured density and also volume flows can be indicated or assigned to one of the out-
puts e.g. current output 2.