SMAR TP303, Operation, Maintenance And Instructions Manual

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Section 4
4.1
MAINTENANCE PROCEDURES
General
Smar
TP303 Position Transmitters are extensively tested and inspected before delivery to the end
user. Nevertheless, during their design and development, consideration was given to the possibility
of repairs being made by the end user, if necessary.
In general, it is recommended that end users do not try to repair printed circuit boards. Spare circuit
boards may be ordered from Smar whenever necessary. Refer to the item "Returning Materials" at
the end of this section.
The table 4.1 shows the messages of errors and potential cause.
SYMPTOM PROBABLE SOURCE OF PROBLEM
Transmitter Connections
Check wiring polarity and continuity.
Check for shorts or ground loops.
Check if the power supply connector is connected to main board.
Check if the shield is not used as a conductor.
It should be grounded at one end only.
Power Supply
Check power supply output. The voltage must be between 9 - 32 Vdc at the TP303 terminals. Noise and ripple
should be within the following limits:
a) 16 mV peak to peak from 7.8 to 39 KHz.
b) 2 V peak to peak from 47 to 63 Hz for non-intrinsic safety applications and 0.2 V for intrinsic safety
applications.
c) 1.6 V peak to peak from 3.9 MHz to 125 MHz.
Network Connection
Check that the topology is correct and all devices are connected in parallel.
Check that two terminators are in good conditions and correctly positioned.
Check that the coupler connections are in good conditions and correctly positioned.
Check that the terminators are according to the specifications.
Check length of trunk and spurs.
Check spacing between couplers.
Network Configuration
Make sure that device address is configured correctly.
NO COMMUNICATION
Electronic Circuit Failure
Check the main board for defect by replacing it with a spare one.
Transmitter Connections
Check for intermittent short circuits, open circuits and grounding problems.
Check if the sensor is correctly connected to the
TP303 terminal block.
Noise, Oscillation
Adjust damping
Check grounding of the transmitters housing.
Check that the shielding of the wires between transmitter / panel is grounded only in one end.
INCORRECT READING
Sensor
Check the sensor operation; it shall be within its characteristics.
Check sensor type; it shall be the type and standard that the
TP303 has been configured to.
Check if process is within the range of the sensor and the TP303 .
Table 4.1 - Messages of Errors and Potential Cause
If the problem is not presented in the table above, follow the note below: