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Tab. 3: The controller's graphic display uses the following symbols:
Symbol
Meaning
[Start/Stop] key pressed
Error
pH setpoint exceeded
2-point controller 1
Acid metered
pH setpoint undershot
2-point controller 1
Alkali metered
ORP setpoint exceeded
2-point controller 2
Oxidant, top
ORP setpoint undershot
2-point controller 2
Oxidant, bottom
Pulse length 1* (acid, alkali)
Control off
Pulse length 1* (acid, alkali)
Control on
Pulse length 2* (oxidant)
Control off
Pulse length 2* (oxidant)
Control on
* controls metering pump or solenoid valve
7.3 Operating structure
n
User qualification: Instructed person, see
‘Users' qualifications’ on page 8
Operating and replacing the storage tank
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