Hanna Instruments Groline HI981412 - Priming the Pump

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PUMP CONTROL
Hi control mode on the HI981412
Set
point
Set
point
Pump statusPump status
Hyst
eresis Hyster
esis
Measured
value
Measur
ed
value
RUNNING RUNNING
NOT RUNNING NOT RUNNING
Pump running continuously
at the congured ow rate
Pump running continuously
at the congured ow rate
Lo control mode on the HI981412
On/O Control
Proportional Control
With Proportional control enabled in SETUP, the dosing time depends on the difference between pH
value and assigned set point.
Set
point
Set
point
Regulator
output
Regulator
output
100% 100%
Band
time
proportional mode
with 0.25L/h
time
proportional mode
with 0.25L/h
Band
speed proportional
0.25L/h
ow rate
SETUP
0.3÷3.5L/h
Flow rate
Set value
Measured
value
Measured
value
Flow rate
Set value
speed proportional
0.25L/h
ow rate
SETUP
3.5÷0.3L/h
0.25L/h
90%
50%15%
0.25L/h
90%
50% 15%
Proportional Control
with Hi Control Mode and Band as illustrated
Proportional Control
with Lo Control Mode and Band as illustrated
An overview of pH proportional control is presented in the graph below.
0.1
8.2. PRIMING THE PUMP
• From measurement mode, long press the arrow keys together to manually activate the pump.
• To exit, release the two keys.
• When there are no errors or active alarm, the LCD backlight is yellow.