wtw Oxi 170, Operating Instructions Manual

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Operation Oxi 170
96 ba24105e08 11/2010
Switching behavior
(normally closed/open)
The relay can be configured as normally closed or open for the
functions
FrC
(Freeze) and
UL
.
LL
(limits). The relay works as normally
open for all other functions.
Note
The switching behavior is set in the configuration level (section 4.4.2).
4.6.2 Limit indicator
Basics With a limit indicator, a relay switches when a specified limiting value is
exceeded or undercut. The switching contact opens or closes
according to the selected switching behavior.
Limit indicators can be used in the following way:
z
Monitoring a limiting value using a relay:
When a limiting value (upper or lower limiting value) is exceeded or
undercut, a relay switches.
z
Monitoring two limiting values using two relays:
If the upper limiting value is exceeded or undercut, a relay switches
and, if the lower limiting value is exceeded or undercut, another
relay switches.
CS
(Cleaning System) The relay controls an external sensor
cleaning unit. The relay works as a closer
(i.e. normally open). During the cleaning
process the measured value is frozen.
The parameterization of the relay is
described in section 4.6.3.
Function Description