SMAR ld301, Operation And Maintenance Instruction Manual

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Section 5
5.1
MAINTENANCE PROCEDURES
GENERAL
SMAR LD301 intelligent pressure transmitters are extensively tested and inspected before delivery to
the end user. Nevertheless, its design includes additional information for diagnosis purposes, in order
to provide an easier fault detection capability and, as a consequence, an easier maintenance.
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.
The sensor has been designed to operate for many years without malfunctions. Should the process
application require periodic cleaning of the transmitter, the flanges may be easily removed and
reinstalled.
Should the sensor eventually require maintenance, it may not be changed in the field. In this case, the
possibly damaged sensor should be returned to
SMAR for evaluation and, if necessary, repair. Refer
to the item "Returning Materials" at the end of this Section.
DIAGNOSTIC WITH THE CONFIGURATOR
Should any problem be noticed relating to the transmitter output, the configurator may carry out
investigation, as long as power is supplied and communication and the processing unit are operating
normally (see Table 5.1).
The configurator should be connected to the transmitter according to the wiring diagram shown on
Section 1, Figures 1.5, 1.6 and 1.7.
ERROR MESSAGES
When communicating using the CONFIGURATOR the user will be informed about any problem found
by the transmitter self-diagnostics.
Table 5.1 presents a list of error messages with details for corrective actions that may be necessary.
ERROR MESSAGES POTENTIAL SOURCE OF PROBLEM
UART RECEIVER FAILURE:
•
PARITY ERROR
•
OVERRUN ERROR
•
ERROR CHECK SUM
• FRAMING ERROR
• The line resistance is not according to load curve.
• Excessive noise or ripple in the line.
•
Low level signal.
• Interface damaged.
•
Power supply with inadequate voltage.
CONFIGURATOR RECEIVES NO
ANSWER FROM TRANSMITTER
• Transmitter line resistance is not according to load curve.
•
Transmitter not powered.
•
Interface not connected or damaged.
•
Repeated bus address.
•
Transmitter polarity is reversed.
•
Interface damaged.
•
Power supply with inadequate voltage.
CMD NOT IMPLEMENTED
• Software version not compatible between configurator and transmitter.
•
Configurator is trying to carry out a LD301 specific command in a transmitter from
another manufacturer.
TRANSMITTER BUSY •
Transmitter carrying out an important task, e.g., local adjustment.
XMTR MALFUNCTION
• Sensor disconnected.
• Sensor failure.
COLD START •
Start-up or Reset due to power supplies failure.
OUTPUT FIXED
• Output in Constant Mode.
• Transmitter in Multidrop mode.
OUTPUT SATURATED •
Pressure out of calibrated Span or in fail-safe state (Output current in 3.8 or 20.5 mA).