GESTRA SPECTORcontrol, Руководство пользователя

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81
Glossary
continued
Cell constant (conductivity control)
The cell constant is a geometric quantity characteristic of the conductivity electrode and is taken into
account when calculating the conductivity. However, this constant may change during operation, e.g.
due to dirt deposits accumulated on the measuring electrode.
If a reference measurement yields a result that differs from the indicated conductivity value, check the
temperature compensation first. Only if the temperature coefficient setting is no longer sufficient for a
correct compensation should you modify the cell constant. In this case, change the cell constant until
the reading and the indicated conductivity match.
24 hour rinsing (conductivity control)
To prevent blocking of the continuous blowdown valve a rinsing pulse is triggered when the mains
voltage is switched on. The continuous blowdown valve is actuated and opens for 2 minutes. After this
period the valve is motored into the CLOSED position where it remains for 2 minutes. The valve is then
motored into the OPERATING position or into the required control position. The process is repeated
every 24 hours. During stand-by operation the time interval continues without triggering the rinsing
pulse. During the rinsing process the MIN limit is not active.
The 24 hour rinsing pulse can be switched ON or OFF.