Manual

13
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 fi rst
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
fi lled 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.