WPI EVOM3 - Page 37

EVOM3
World Precision Instruments 33
Issue
Possible Cause Solution
STX2-PLUS
electrode tips over
when released
The cable is heavy
and can cause the
electrode to tip over
if too much cable is
in the air.
Lay the cable on the tabletop as close to the electrode head as
possible.
The reading appears to be drifting*
(ee the dit definitin el)
The electrodes are
coated with depos-
its from the use of
DMEM.
he eletde eie enmati leaning
he id temea-
ture in the plate is
changing.
Use a plate warmer.
In a 5% CO
2
envi-
ronment, a loss of
CO
2
causes the me-
dia pH to change,
and the resistance
reading may in-
crease sharply.
A 5% CO
2
environment can help in reducing pH media
changes.
The electrode read-
ing is unstable. (see
the tailit defini-
tion below).
The electrodes are
coated.
he eletde eie enmati leaning
The electrodes
need to be
chlorided.
he eletde eie hliding ee Rehliding the le-
trodes" on page 27.
Radi een
interference
n   me an ellla hne athe aa m the
experimental setup.
---- appears
on the screen
Resistance reading
is out of range
An out of resistance range will display ---- on the screen. Adjust
the range to correct the error. A saved well will read a space
(“ “) if the display is out of range. Go to Setup , Mode Units and
increase the resistance range. See page 11.
NOTE: The EVOM3 ill ead nl at  ae K Ω
NOTE   hae a lemie ith that all tide the definitin  thi
troubleshooting section, contact the WPI Technical Support team at 941.371.1003 or
technicalsupport@wpiinc.com.
itReading that ntinl ineae  deeae a ignifiant ale (eithe
voltage or resistance) over time. Example 1: At 10 mV the PD reading is increasing
mVminte ( dit   mVminte i aetale) amle  t  Ω the
eading i ineaing  Ωminte ( dit   Ωminte i aetale) eie
drift may be caused by a coated electrode, pH or temperature changes. See the
Troubleshooting entry on drifting above. Also see "Instrument Diagnostics and
Calibration" on page 21 or "Testing the STX2-PLUS Electrodes" on page 28.