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SITRANS LC500 – OPERATING INSTRUCTIONS
7ML19985GE04
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Maintenance
Test function
Auto Self-testing
SITRANS LC500 continuously performs a variety of tests to verify that the device is
functioning correctly. These include a test where a known capacitor is applied to the
input of the device. The internal results must match the known capacitance value. If a
deviation is detected the Fault/Failure can be flagged with a pre-set loop-current (user
configurable) and as a status in each HART message.
Manual testing
In order to test the proper processing of signals in PLC/DCS equipment, SITRANS LC 500
allows you to invert the output signal status. In Menu 11, when both buttons are pressed
simultaneously, the signal outputs switch to their opposite state. When the buttons are
released, the outputs revert to the initial state.
If no Fault/Failure is present and no buttons are pressed, the display for menu 11
alternates between two test patterns which together illuminate all the segments of the
display. If the loop-current control is in analog mode the loop current will hold the last
value, during this test.
Inspections
Under normal circumstances, the SITRANS LC500 transmitter requires no maintenance.
However, we recommend that you schedule periodic inspections of SITRANS LC500.
The inspection can be subdivided into two parts:
1.
Visual Inspection: confirm the following conditions:
a. Inside enclosure is clean and dry.
b. Enclosure sealing is intact and functioning properly (not hardened).
c. All screw connections are tight.
d. Ground connections inside the housing are solid.
e. Ground connections outside the housing are solid.
Note:
If a Fault or Failure is present, its signal will take precedence over the test
function.