CorrTran MV Corrosion Monitor
50
Device Status
Codes
Description
Troubleshooting
LPR only mode
The CorrTran MV has been configured
to operate in LPR mode for its general
corrosion calculation.
Device mode is by default Normal
(HDA/LPR) and should be left that way
to maintain the best accuracy for all
process variables. See section 3.3.2 for
more information.
High localized
corrosion
detected
The localized corrosion rate is above
0.3.
Information only.
B value from
Harm. Out of
range
The calculated B value based on the
HDA is out range (10mV<B<62.5mV).
In some rare occasions the HDA
calculation might not give a plausible
result. Switch to LPR only mode if this
flag persists to stay on. See section
3.3.4 for more information.
Conductance out
of range
The measured solution conductance
is lower than 4 μS. This equals a
conductivity of approximately 1 μS/cm
for finger electrodes.
The CorrTran MV needs at least 4 μS
of solution conductance or solution
conductivity of 1 μS/cm for full
accuracy. This can also be an indication
that there is too much build up on the
surface of the electrodes and they may
need to be cleaned or they may not be
fully immersed in the process fluid.
Cell offset
voltage overflow
The CorrTran MV has detected
a voltage difference between the
three electrodes which is too high to
compensate.
Typically this is an indication that there
is too much build up on the surface
of the electrodes and they need to be
cleaned or that they have exceeded
their useful life and should be replaced.
Corrosion rate
calculation not
possible
The CorrTran MV was not able to get
any useful data.
Check the electrodes for debris, check
for other flags, and make sure that the
electrodes are fully immersed.
Electrode
balance out of
range
Due to an extremely high unbalanced
potential (voltage difference) of the
electrodes, the CorrTran MV is drawing
more power from the loop than
available.
One way to deal with this problem is
to set the loop current to a fixed value
(max is 20 mA). This should only occur
under very rare circumstances, where
the corrosion rate is very small (loop
current is approx. 4 mA) but at the
same time there is a huge potential
difference between the electrodes. This
can indicate contamination of one or
more electrodes, corrosion masking
effects of buildup, or that one electrode
is bent or missing from the probe.
Harmonics out of
range
The HDA did not provide any valid
results.
In some rare occasions the HDA
calculation might not give a plausible
result. Switch to LPR only mode if this
flag persists to stay on. See section
3.3.4 for more information.
Internal failure
Hardware failure detected
Replace transmitter
ADC failure
ADC failure detected
Replace transmitter
Memory failure
Memory failure detected
Replace transmitter
Table 5. Device Status Codes Troubleshooting Guide (continued from previous page)
