K-Patents PR-23 - Manual (Page 63)

6 Configuration and calibration 55
6.7.2 Setting prism wash parameters
To set the prism wash parameters for a given sensor, first select the sensor, then se-
lect
5 CALIBRATION from the Main menu, and then 4 PRISM WASH . This menu contains the
alternatives (factory settings are given in parentheses):
1 PRECONDITION TIME 0–30 s (0 s)
2 WASH TIME 0–30 s (3 s)
3 RECOVERY TIME 0–120 s (20 s)
4 WASH INTERVAL 0–1440 min (20 min)
5 WASH CHECK MODE (Disabled)
6 HOLD DURING WASH (Active)
7 TEMP LIMIT ACTIVATION
8 TEMP LIMIT VALUE °C
9 EMPTY PIPE CHECK (Active)
0 MORE ...
1 WASH nD LIMIT
2 WASH TOLERANCE TIME (0 min)
The prism wash cycle: See Figure 6.16 and Section 6.7.1. The timing of the wash cycle
is controlled by the
WASH INTERVAL , PRECONDITION TIME , WASH TIME and RECOVERY TIME settings. If
the WASH INTERVAL is set to zero, the wash can be initiated only by using the manual wash
or remote wash request.
If the PRECONDITION TIME is zero (or there is no relay configured for preconditioning), the
preconditioning phase is skipped. If the WASH TIME is zero (or there is no relay for wash),
the wash functionality is completely disabled.
The recommended wash times and wash medium pressures are given in Section 4.2.1,
“Recommended wash pressures and times”.
Wash check: The prism wash check monitors automatically that the wash really has
an effect on the prism. In the
WASH CHECK STANDARD mode, prism wash is accepted if the
refractive index n
D
either falls below wash nD limit (default 1.34) at NORMAL OPERATION or
NO SAMPLE occurs. This is the indication of a successful wash with water or steam.
If the wash is not accepted, the diagnostic message PRISM WASH WARNING (see Section 8.4)
will appear. If no wash is accepted during wash tolerance time, the message becomes
PRISM WASH FAILURE . Both messages and the wash tolerance counter are reset by a suc-
cessful wash.
The
WASH CHECK AUTOMATIC WASH CUT mode 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 6 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.
To activate (or deactivate) a temperature limit, choose 7 TEMP LIMIT ACTIVATION and
then the appropriate command in the menu.