Burkert Type 8620 - Manual (Page 67)

mxCONTROL Type 8620
Page 67
→ Hold the current PV during the calibration procedure: Yes or No
(Default: Yes).
Hold-Function – for calibration without interrupting the process:
it holds the PV constant during the whole calibration procedure.
Therefor the current PV is used when starting the calibration
procedure with confirming “Next Step”.
→ Proceed with “Next Step”, press key “OK”
→ Then rinse/clean the electrode as requested, after that press key “OK”
→ Scroll to “1stPoint”, press key “INPUT”.
→ Put
the electrode into 1
st
buffer solution and input the value of this buffer
solution (care for temperature dependence), confirm with “OK”.
→ Wait until the measured PV has a steady value, then
→ Proceed
with “Next Step”, press key “OK”
The controller measures the current PV of the 1st buffer solution and the corres-
ponding current I_1.
→ Then rinse/clean the electrode again as requested, after that press key
“OK”
→ Scroll to “2ndPoint”, press key “INPUT”.
→ Put
the electrode into 2
nd
buffer solution and input the value of this buffer
solution (care for temperature dependence), confirm with “OK”.
→ Wait until the measured PV has a steady value, then
→ Proceed
with “Next Step”, press key “OK”
The controller measures the current PV of the 2 nd buffer solution and the corres-
ponding current I_2 …
… and calculates Offset and Slope values.
(The item “Calib failed” is only displayed if calibration failed: Slope could
not be calculated. In that case start the calibration procedure again.)
→ Rinse/clean the electrode again before putting back into process fluid.
→ Finish calibration and the Hold Function of PV with “End”, press key “OK”
Calibration Mode “Manual”
This calibration mode can be used for the calibration of 4-20mA input signals in case of known Slope
and Offset values.
→ Input the values of
Offset in [Scal Unit] at 4 mA, then press key “INPUT”and
Slope in [Scal Unit]/[mA], then press key “INPUT”.
→ For setting back the values to default values press key “YES” for a few seconds
(password protected: for Specialist only)
→ Finish calibration with “End”, press key “OK”