K-Patents PR-03 User Manual
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PR-03 instruction manual
5.9.1 Timed wash
When an external relay unit is used as a wash timer, the time settings are entered after the sequence Cali-
brate / Parameters / Prism wash
:
− Preconditioning time s (0)
− Wash time, s (3)
− Recovery time, s (30)
− Wash interval, min (20)
The default values for timed wash are given in parenthesis. The output signal is locked during wash and
recovery time.
WASH
RECOVERY
INTERVAL
PRECOND.
Figure 5.12
Prism wash sequence
Note:
The wash interval timer starts a wash at a preset interval after last wash, independently of how the
last wash was initiated. If the wash interval is set to zero, the timer will not initiate a wash.
Wash type
Time
Pressure
Recovery
Interval
Steam wash
3-5 sec.
5-6 bar (73-87 psi)
20-30 s
20-30 min
High pressure water wash
10-15 sec.
20-30 bar (290-435 psi)
20-30 s
10-20 min
Table 5.1
Recommended prism wash times for the PR-03 sensors
Important:
In steam wash, do not exceed the recommended wash times, because some process media may
burn to the prism surface if steamed for longer time. In case of coating, shorten the wash interval.
5.9.2 Smart wash
Sometimes it is necessary to modify the standard wash routine to fit the application better. The Smart wash
feature allows you define better when wash is needed and when it should not be implemented.
The Smart wash starts the wash when the prism shows signs of being coated. An early indicator of beginning
coating is that the Slope decreases. Slope is a measure of the sharpness of the optical image (Section 5.5.4).
The Smart wash settings are made at Calibrate / Parameters / Prism Wash / Smart
wash
:
Slope limit
A wash is initiated when the Slope value goes below this limit. The Slope limit has to
be set based on observations of slope values both at clean prism and at slight coating.
When the slope limit is set to zero, this Smart wash function is inactive.