Watts HF scientific CLX- XT, Owner'S Manual

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CLX-XT (28652) Page 26
REV 5 (5/2020)
8.4 Standby Reagent Purge (Software Option Cat #25316)
During times when the CLX-XT is not being operated such as in voyage between
ballasting and deballasting no reagent moves past the check valves. In some instances this
can cause these parts to clog. To prevent this occurrence a single pump action is enabled at
a timed interval.
It is important that the unit remain in Standby Mode and power is always applied.
This software feature is available on select software packages where either Modbus or the
Hardware Remote Standby feature is used.
Every time the instrument is placed in standby mode a timer starts. Once the set time has
elapsed a single action of the reagent pump occurs to keep the check valves clear. This
single will inject about 25
µ
L of each reagent into the chamber. This is performed with a
special pulse width modulation to prevent the reagent from splattering and staining the
measurement glass.
Note that for the timer to be active, power must be constantly applied to the instrument. If
the power is removed or a power disturbance occurs the timer is reset.
The default factory time setting is once every 24 hours. This time period can be adjusted if
desired at Modbus Address 40025 which is an integer. The allowable setting range is 1
hour to 100 hours.
8.5 Reset Reading to Zero (Software Option Cat # 25316)
If there is a need to reset the reading to Zero this can be accomplished in most software
packages through Modbus. The address is 00006. The default setting is false (0) setting
this to true (1) will set the reading to Zero and the completion on the next cycle. This
setting also affects the 4-20mA output and alarms.
8.6 AutoPurge (Hardware option Cat# 25279)
If power is removed from the CLX-XT without stopping the unit first, there is a good
chance that sample water and possibly reagents are left in the optics. Over a period of time
this can stain the cuvette. This factory installed option stores a charge in a super-capacitor.
During an unexpected removal of power the stored charge is used to open Purge solenoid.