LaMotte TRACER pH PockeTester 1741, Manual

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Troubleshooting
Problem Cause Action
Power on but
no display Batteries Insert batteries
Batteries Verify correct polarity
Batteries Replace batteries
Unstable
readings Electrode Immerse electrode more deeply in sample
Electrode Condition electrode before first use
Electrode Remove air bubbles caught under
electrode
Electrode Clean electrode
Electrode Replace electrode
Slow
response
time or
reading drift Clogged junction Soak in 4.07M Potassium Chloride (KCl)
at 60°C for 30 minutes
Strong alkaline
measurement Soak in 0.1M Hydrochloric acid (HCl)
overnight
Deteriorated gel layer Replace electrode
Protein coating on
electrode surface Soak in 1g Pepsin dissolved in 10 mL of
0.1M HCl for 30 minutes or as needed
Oil, paint, dyes,
suspended solids on
electrode Rinse electrode alternately with materials
solvent then a buffer 7.00
Dry bulb Dehydrated membrane,
long term storage
without wetting Soak electrode tip in wetting cap filled
with 1 mL 7.00 buffer for 24-48 hours
Static charge Wiping electrode Rinse electrode in 7.0 buffer and blot. Do
not wipe electrode
Same
readings in
different
buffers and
samples Cracked or broken
electrode Replace electrode. Use bulb guard. Avoid
plunging electrode into bottom of
container and stir bars.
Erratic LCD
display Samples have low ionic
strength (lack salt); e.g.
distilled, deionized,
boiled, lake water (high
pressure) For each 50 mL of sample add 1 drop (50
m
L) of saturated Potassium Chloride
(KCl). No alteration in pH will occur by
inert KCl.
Unexpected
readings Buffers Calibrate with fresh buffers
Buffers Calibrate with buffers that bracket sample
pH
Display
frozen HOLD function Press MODE/HOLD or turn meter off
Button response Remove batteries press ON/OFF button
for 3 seconds. Reinsert batteries (stored
data will be lost)
Steady “
-1
”
display
Wait Reading not stable yet
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