TLM100 User’s Manual
Page 14
Revision 1.5
Symptom
Troubleshooting Procedure
No tank level
output
1. If operating in the
NMEA 2000
®
Mode
, check the connection to the
NMEA 2000
®
interface (see Section 2.5.1) and tighten if necessary.
2. Ensure that power is supplied to the NMEA 2000
®
network. Proper
network power can be checked by measuring the voltage at an open
tee between NET-S and NET-C. The voltage should be between 9 and
16 volts.
3. Ensure that both trunk line terminators are in place. Proper network
termination can be checked by removing network power and
measuring the resistance at an open tee between NET-L and NET-H
signals. The resistance should read approximately 60 ohms (two 120
ohm terminators in parallel equals 60 ohms).
4. Remove the TLM100 sensor component from the tank opening and
ensure that the surface of the ultrasonic sensor is not fouled.
Inaccurate tank
level output
1. If operating with a rectangular tank, ensure that the tank depth is
programmed properly (see Section 3.4.1).
2. If using custom calibration, re-calibrate the TLM100 (see Section
Erratic
Readings
1. Remove the sender and place it on top of a standard paper towel roll
core. Be sure the towel core is on a hard surface. Reset the unit to
factory defaults using either a DSM250 display or N2KAnalyzer.
Power the unit up and wait for two minutes. The tank level value
should read 70-80% (this number can vary depending on the paper
towel roll dimensions). If you see a depth reading in this range, the
sensor is operational, so please follow the next steps in this
sequence.
2.
Determine if the sensor’s gasket is installed properly. Only a Maretron
TLM100 gasket should be used. The TLM100 is not compatible with
cork gaskets, silicone sealant, or metal fittings. The gasket only lines
up a single way. A clear line of sight should be observed through all of
the mounting holes with the gasket installed.
3. The TLM100 transmits sensor signals at a 6° angle. Think of the
signal path as a cone getting progressively wider the deeper the tank
is. There must not be any obstructions within this cone like baffles,
return lines or clean out pipes.
4. Sloped or grooved tank bottoms will cause an issue with a signal
return when the tank is empty, causing the TLM100 to transmit an
inaccurate or erratic reading or no reading at all. As long as there is
some fluid providing a flat surface to reflect the signal, you should
receive a valid reading. If your tank bottom is sloped or grooved, you
should install a focus tube with a focus tube cap in order to ensure
that there will be a reading when the tank is empty.
Figure 8
– Troubleshooting Guide
If these steps do not solve your problem, please contact Maretron Technical Support (refer to
Section 7 for contact information).