GE Ettan IPGphor 3 Operating Instructions Manual page 110

7 Troubleshooting
Symptom
Power delivery
Current too low or zero
Voltage limit not reached
Sparks or burning in strips
110
Possible solution
At least two of three pressure pads under the
safety lid should press gently against the strip
holders to ensure electrical continuity between
the strip holder electrodes and the electrode areas
on the platform.
The gel must be evenly and completely rehydrated
to conduct current. Make sure the proper amount
of rehydration solution is applied to the IPG strip
holder and allow a minimum of 10 hours for rehy-
dration.
Check that both connecting points of the strip
holder or the connecting pins of the manifold
electrodes are in contact with the gold surface.
The ionic strength of the rehydration solution is
too high. The instrument has reached the current
limit; reduce the IPG buffer concentration; use a
mixed-bed ion-exchange resin to remove ionic
breakdown products of urea of other additives.
Desalt the sample or prepare the sample so that
the salt concentration is less than 10 mM.
Reduce the current limit. Do not exceed 50 μA per
strip.
Prevent the IPG strip from drying out by always
applying Immobiline DryStrip Cover Fluid during
rehydration.
Ensure that the IPG strip is fully rehydrated along
the entire length of the strip. The IPG strip should
be in complete contact with the correct volume
of rehydration solution. Remove any air bubbles
trapped under the IPG strip.
Desalt the sample or prepare the sample so that
the salt concentration is less than 10 mM. De-
ionize additives to the rehydration solution. Exces-
sive charged material in the sample or rehydration
buffer lead to electro-endosmosis which will dry
out the middle of the strip, possibly leading to
arcing and burning at these points.
Ettan IPGphor 3 Operating Instructions 28-9635-51 AC