Hach Chlorine Sensor User Manual page 12

4. Push the ENTER key and select Activate TMR.
5. Set the amount of time a measurement(s) can be outside the
deviation range before an alarm occurs:
Option Description
ALL ACTIVATE TMR: Sets the amount of time the chlorine AND pH
measurements can be out of range before an alarm occurs-10 to
99 minutes (10 minutes default).
CONFID LEVEL: Set the percentage rate at which chlorine AND
pH measurements must be out of range before an alarm occurs
and must be in range before an alarm is automatically canceled
by the instrument-50 to 95% (default).
CL2/pH ACTIVATE TMR: Sets the amount of time the chlorine OR pH
ONLY measurements can be out of range before an alarm occurs-10 to
999 minutes (30 minutes default).
CONFID LEVEL: Set the percentage rate at which chlorine OR
pH measurements must be out of range before an alarm occurs
and must be in range before an alarm is automatically canceled
by the instrument-50 to 95% (default).
LCC ACTIVATE TMR: Set the amount of time a chlorine measurement
can be 0.5 ppm or higher before an alarm occurs-10 to
999 minutes (30 minutes default). An alarm only occurs if the
previous chlorine sensor calibration was done using a process
flow with a low chlorine concentration (LCC) (< 0.5 ppm).
CONFID LEVEL: Set the percentage rate at which chlorine
measurements must be 0.5 ppm or higher before an alarm
occurs and must be less than 0.5 ppm before an alarm is
automatically canceled by the instrument-50 to 95% (default).
6. Push the ENTER key and select Deactivate TMR.
7. Set the amount of time an alarm is on before it is automatically
canceled (deactivated) by the instrument if the measurements go
back in to range at the percentage rate (confidence level) selected in
Activate TMR:
Option Description
ALL Sets the amount of time a chlorine AND pH measurement
deviation alarm is on before it is canceled-10 to 99 minutes
(30 minutes default).
12 English
Option Description
CL2/pH Sets the amount of time a chlorine OR pH measurement
ONLY deviation alarm is on before it is canceled-10 to 999 minutes
(30 minutes default).
LCC Sets the amount of time an LCC alarm is on before it is
canceled-10 to 999 minutes (30 minutes default).
8. Push the ENTER key and select CL2 Deviation.
9. Set the chlorine measurement deviation values that activate alarms:
Option Description
CL2 ERR DEV Set the chlorine measurement deviation that will activate an
error alarm-30 to 99% (50% default).
CL2 WRN DEV Set the chlorine measurement deviation that will activate a
warning alarm-10 to 30% (20% default).
Note: Chlorine deviation is measured by the instrument using the chlorine
value recorded during the last process concentration calibration for chlorine.
10. Push the ENTER key and select pH Deviation.
11. Set the pH measurement deviation values that activate alarms:
Option Description
pH ERR DEV Set the pH measurement deviation that will activate an error
alarm-1 (default) to 3 pH units.
pH WRN DEV Set the pH measurement deviation that will activate a
warning alarm-0.5 (default) to 1 pH unit.
Note: pH deviation is measured by the instrument using the pH value recorded
during the last process concentration calibration for chlorine.
Calibrate the sensor
About sensor calibration
The sensor characteristics slowly shift over time and cause the sensor to
lose accuracy. The sensor must be calibrated regularly to maintain
accuracy. The calibration frequency varies with the application and is
best determined by experience.