USF Wallace & Tiernan DEPOLOX 4, Руководство пользователя

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8. TROUBLESHOOTING
22
PROBLEM CAUSE REMEDY
Insufficient sensitivity Insufficient water flow.
Contaminated electrodes.
Changed grit colour
(yellow/brown).
Excessive pH-value
Check water flow, remove any
contaminants in sample water line
or in measuring cell, clean strainer.
Clean electrodes.
Replace grit.
Adjust pH-valve.
Unsteady signal. Membrane clogged. Air
bubbles on inner surface of
membrane. Replace membrane. Wait until
running-in period of measuring cell
is completed.
Calibration of zero
point and measuring
range not possible. Excessive zero current.
Insufficient measuring cell
current.
Measured electrode current (menu
item µA electrode current) in
chlorine-free water must be below
± 5 µA; otherwise verify bias
voltage = 250 mV (chapter 6.2).
The current potential between
chlorine-free and chlorinated water
with 1.0 mg/l of chlorine must be at
least 4 µA; contaminated
electrodes or the presence of
chlorisocyanurates in the water
might be the cause of a lower
potential.
Indicated value
oscillates considerably
at constant chlorine
concentration. Considerable fluctuations in
water pressure.
Fluctuating pH-value.
Inlet to cell body or flow
regulator clogged.
Diaphragm defective.
Air bubbles.
Check pressure.
Clean pH electrodes.
Clean inlet or flow regulator.
Replace diaphram.
Install vent line.