Float faulty
switch point
Replace
Tank level sensor does
not function (fault 128
or 129)
Not connected
Connected wrongly
Sensor faulty
Input circuit faulty
Check wiring to controller
Check wiring polarity and
correct if needed
Test with loop calibrator,
replace sensor if necessary
Test with loop calibrator,
replace PCB if necessary
DO NOT – Bridge the sensor
input with wire, this will destroy
the input circuit!
Tank Level sensor
reads incorrectly
Cable vent tube blocked or
sealed
Wrong sensor specification
installed
Sensor faulty
Parasitic interference from
nearby cables
Ensure vented section of cable
terminates to atmospheric
pressure
Replace with original OEM spec
part
Test with loop calibrator,
replace if necessary
Ensure cable is shielded all the
way OR Separate sensor cable
from lighting and motor supply
cables OR adjust probe
sensitivity setting to
compensate
NOTE – A loop calibrator is used for testing sensors and sensor inputs by drawing or measuring between
4mA and 20mA of current. Do not confuse this with an electricians loop impedance tester, which is
designed to measure the impedance of the mains electrical supply system. Do not confuse this either
with shorting the input with a piece of wire (sometimes referred to wrongly as a “loop test”), this will
damage the input circuit.
Fuse Listing
F1 – 500mA 20mm quickblow
F2 – 1A 20mm glass passivated
F3 – 10A 20mm glass passivated
F4 – 10A 20mm glass passivated
F5 – 10A 20mm glass passivated
F6 – 10A 20mm glass passivated
TC Series Controller v1.30
www.3ptechik.co.uk
09-August-2017
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