Troubleshooting guide
80
Reference Manual
00809-0100-4308, Rev BA
Section 6: Service and Troubleshooting
December 2014
Service and Troubleshooting
6.3.2 Incorrect or missing interface level reading
Symptom Possible cause and recommended actions
Incorrect Interface Level reading.
The Upper Product Dielectric Constant is not
correct, see “Upper Product Dielectric
Constant” on page 163.
Air gap is too big when the Measurement
Mode is set to Interface Level with
Submerged Probe. Reduce air gap or switch
the Measurement Mode to Product Level and
Interface Level.
Missing Interface Level reading (reported as
NaN).
The Measurement Mode is set to Product
Level. Set Measurement Mode to Product
Level and Interface Level, refer to
“Measurement Mode” on page 162.
The Interface Peak is difficult to detect,
because the bottom product has a low
dielectric constant, or the signal is
attenuated in the upper product. Check
Thresholds. For more information, see
“Example 2: Interface Peak not found” on
page 88.
There are two products in the tank, but only
the product surface or interface is detected.
The upper product is too thin to be detected.
No action is needed. See “Interface
measurements” on page 106 for minimum
interface thickness for different probe types.
Check Thresholds, see “Adjusting
thresholds” on page 84.
There are two products in the tank, but no
readings are reported.
Check Thresholds, see “Adjusting
thresholds” on page 84.
There is only oil in the tank but the transmitter
reports water.
Check Thresholds, see “Adjusting
thresholds” on page 84.
Make sure the Typical Interface Condition is
set to Layer at the bottom (thin) if you
typically have a thin layer at the bottom, see
“Typical Interface Condition” on page 164.
There is only water in the tank but the
transmitter reports oil.
Check Thresholds, see “Adjusting
thresholds” on page 84.
Make sure the Typical Interface Condition is
set to Layer on Top (Thin) if you typically have
a thin layer at the top, see “Typical Interface
Condition” on page 164.