Sensor Requirements; System And Measurement Operation - Mettler Toledo thornton Bedienungsanleitung

pureO Dissolved Ozone Sensor
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Sensor Requirements

Ozone sensors require a period of polarization at first start-
up in the presence of ozonated water before they develop
a signal. They require additional time to achieve stability.
During polarization, readings can remain at zero for as
long as 45 minutes after ozone is first introduced and then
the sensor signal will rise to its steady-state response level
when calibration can be performed. If a large volume hold-
ing tank is in the recirculation loop, additional time may be
needed for its ozone concentration to stabilize.
Once a sensor has been polarized, that condition will be
held for a long period, even when zero ozone is present.
Re-polarization is necessary only if the sensor is unpow-
ered from the transmitter for more than ten minutes or if the
electrolyte or membrane is replaced.

System and Measurement Operation

Polarization of sensors at measurement points 2 and 3 (re-
fer to Figure 1 on page 6) above may be difficult because
of low ozone concentration during normal operation. It is
recommended to install and operate the pureO
ing an ozone sanitization that lasts long enough to achieve
full polarization.
Alternatively, if the sensor flow housings are mounted close
together, it may be possible to temporarily place the point
2 and point 3 sensors, one at a time, into the flow housing
for point 1. This must be done without disconnecting the
sensors' electrical connections. This process allows polar-
ization of those sensors in ozonated water during normal
operation.
© 07 / 16 Mettler-Toledo GmbH
Printed in Switzerland
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Dissolved Ozone Sensor
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pureO
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