Endress+Hauser PROline promag 23, Operating Instructions Manual

Page: 54 / 108

6 Commissioning PROline Promag 23
54 Hauser
6.2.2 Empty-pipe/full-pipe calibration
Flow cannot be measured correctly unless the measuring tube is full. This status can be
monitored at all times with the Empty Pipe Detection function (EPD).
The EPD function cannot be activated until
after empty/full pipe calibration has been
performed. This adjustment procedure is described below.
!
Note:
The EPD function is not available unless the sensor is fitted with an EPD electrode.
The sensor is calibrated ex-works with water, i.e. at approximately 500 S/cm. If the
fluid conductivity differs from this reference, empty pipe/full pipe calibration has to be
performed again on site.
The default setting for EPD when the devices are delivered is OFF; the function has to
be activated if required.
An EPD process error can be output by means of the pulse/frequency output.
Response to partially filled pipe
If EPD is on and trips in response to a partially filled or empty measuring tube, the
message “EMPTY PIPE” appears on the local display.
The EPD process error is defined ex-works as a “notice message” and has no effect on
the outputs of the measuring device (see Page 46).
If the pipe is partially filled or empty and EPD is not on, response can vary in identically
configured systems:
Flow reading fluctuates
Zero flow
Excessively high flow readings
Performing empty-pipe and full-pipe calibration (EPD)
!
1. Select the appropriate function in the function matrix:
Block BASIC FUNCTION
PROCESS PARAMETER ADJUSTMENT
EPD ADJUSTMENT
2. Empty the piping. Make sure that the wall of the measuring tube is wetted with
fluid for the calibration procedure.
3. Start empty pipe calibration:
Select “EMPTY PIPE ADJUST” and press
F
to confirm.
4. Fill the pipe with fluid.
5. Start full pipe calibration with the fluid at a standstill:
Select “FULL PIPE ADJUST” and press
F
to confirm.
6. Once calibration is completed, switch EPD on Select “ON” (flashing) and
press
F
to confirm.
"
Caution:
The calibration coefficients must be valid before you can activate the EPD function.
If calibration is incorrect the following messages might appear on the display:
– EPD FULL = EMPTY
The calibration values for empty pipe and full pipe are identical.
In this case you must repeat empty-pipe or full-pipe calibration!
– EPD ADJUSTMENT NOT OK
Calibration is not possible because the fluid's conductivity is out of range.
In cases of this nature you must repeat empty-pipe or full-pipe calibration!