deltawaveC-P
User manual
systec Controls Mess- und Regeltechnik GmbH 62/139
www.systec-controls.de
8.6.3. Deleting the zero value
In the main menu
, select "Zero Setup" - "Zero" - "Delete zero". This action
deletes your zero calibration and resets the device to factory settings
.
Once the zero offset has been set it will remain in the
system until it will be deleted or a new zero offset will have
been set. Please consider this for your next item. We
recommend to make new zero setting at each new
measurement when possible.
In the course of zero calibration with closed pipe valves, your
deltawaveC-P calculates the transit-time differential that may
develop between the transducers and any residual flow. This
calculated time (including zero) is automatically included for
subsequent calculations during flow measurement. This method
enhances the precision of your flow measurements. If it is not
possible close the pipe valves, delete the zero value that may
have been set previously. If anything prevents you from
performing a zero calibration, you will have to take the
corresponding imprecision into account in your measurements.
The zero setpoint is retained in device memory until it is
overwritten with a new zero setpoint. If it was possible to close
the pipe valves, check the "Flow" column in one of the three
measuring window to determine whether or not the flow rate is
going down. You should not perform a zero calibration until a
settled value is output to the flow display. A stop valve is not
available at all positions of the piping. The tolerances that
develop during installation, including tolerances of the ultrasonic
transducers and pipe data, will lead to a certain zero offset error
in the measuring equipment. Provided meticulous care was
taken during installation, the flow velocity error should stay
within the range from 0.00 m/s to 0.03 m/s. The zero offset error
is reduced in proportion with increasing pipe size.