Vaisala MI, Инструкция по эксплуатации

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7 Prism wash
71
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becomes
PRISM WASH FAILURE
. Both messages and the wash tolerance counter are re-
set by a successful wash.The Wash check mode, automatic wash cut differs from the
standard mode by stopping the wash 2 seconds after the n
D
falls below the limit.
To stop the measurement for the duration of the prism wash , choose
MEASUREMENT
HOLD DURING WASH
and in that menu activate the hold function. The CONC reading and
mA output are held in the value they had immediately before starting the wash cycle.
You can also stop temperature measurement for the duration of the wash by setting
TEMPERATURE HOLD DURING WASH
.
To set a low temperature limit , choose
WASH INHIBIT TEMPERATURE ENABLE
, enable it (fac-
tory setting is disabled) and then set the temperature with
WASH INHIBIT TEMP VALUE
. The
temperature is in the units that is chosen from the Calibration menu as the secondary
unit.
The empty pipe check prevents washing if message is
NO SAMPLE
, i.e. there’s no
process liquid in the pipe . To deactivate (or activate) the empty pipe check, choose
EMPTY PIPE CHECK
and then the appropriate menu command.
To change the wash nD limit , select
WASH VERIFY ND LIMIT
to set the n
D
to be used by the
wash check functionality.
If you have set a wash verify delta nD limit , a temporary wash verify limit is calculated
in the beginning of wash: n
D limit
= n
D current
– Δn
D
. This temporary limit is compared to
actual wash verify nD limit parameter, and the higher of these values takes precedence.
To set wash tolerance time , select
WASH FAILURE TOLERANCE
to set the time during which a
wash has to be accepted. If no wash is accepted during wash tolerance time, the mes-
sage becomes
PRISM WASH FAILURE
. The wash tolerance counter is reset by a successful
wash.