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8.
Operating mode
8.1.
Time-controlled measurement and offline function
Assuming that the measurement pause has not been set to 0 minutes in the "interval" parameter
menu, a (steady) measurement is carried out at the interval of the parameterized measurement
pause.
The measuring process begins after switching on the device by measuring the raw water hard-
ness. The soft water measurements follow until the measured value of the sensor has stabilized
(steady measurement). Further hardness measurements are carried out according to the para-
meterized measurement pause between two hardness measurements.
If the set hardness limit is exceeded, a counter measurement is carried out in the raw water to
check. If the set hardness limit is exceeded, a limit alarm is triggered. The corresponding relay
output is switched after the set alarm delay has elapsed.
If the result of one of the following hardness measurements falls below the hardness limit value,
the limit value alarm is automatically reset. The measurements are then continued continuously
until the limit value has been undershot.
The device can be switched to offline mode via a potential-free contact (offline contact). No
hardness measurements are made in this state.
8.2.
Water meter or release controlled measurement and offline function
Provided that the measurement pause has been set to 0 minutes in the parameter menu "inter-
val", the soft water measurements are carried out as long as a flow is detected.
The flow is recognized and evaluated by the impulses of an externally connected contact water
meter. Alternatively, instead of a contact water meter, an external potential-free closer (release
contact) can be used for continuous measurement.
To activate this mode, set the interval to 0 minutes and connect an external potential closer to
terminals 31 and 32. With an active short-circuit on terminals 31 and 32, the water hardness is
continuously determined. This mode works in the same way as the water meter controlled mea-
surement.
This makes it possible to enable process or flow-dependent monitoring of the soft water in the
absence of a contact water meter.
The measuring sequence is similar to the measuring sequence of the time-controlled measure-
ment. The only difference is that measurements are not time-controlled, but are triggered via a
connected potential-free contact water meter (connection terminals 27 and 28). After the mea-
sured value of the sensor has stabilized in the soft water, the device waits for further water meter
pulses. A soft water measurement takes place with each pulse.
Regardless of whether a contact water meter or a release contact is connected, the offline contact
can be used to stop the measurement as long as this contact remains closed. No hardness mea-
surements are made in this state.