SMAR ld301, Operation And Maintenance Instruction Manual

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Operation
2.5
Output
Calculates the current proportional to the process variable or manipulated variable to be
transmitted on the 4-20 mA output depending on the configuration in OP-MODE. This block also
contains the constant current function configured in OUTPUT. The output is physically limited
to 3.6 to 21 mA.
Current Trim
The 4 mA TRIM and 20 mA TRIM adjustment is used to make the transmitter current comply
with a current standard, should a deviation arise.
User Unit
Converts 0 and 100% of the process variable to a desired engineering unit read out available
for the display and communication. It is used, e.g., to get a volume or flow indication from a
level or differential pressure measurement, respectively. A unit for the variable can also be
selected.
Totalization
Used for flow to application totalize the accumulated total since the last reset, getting the
volume or the transferred.
The totalized value is persistent; the totalization may proceed even after a power failure. Only
the totalization residue value is discarded.
Display
Can alternate between two indications as configured in DISPLAY.
THE DISPLAY
The integral indicator is able to display one or two variables, which are user selectable. When
two variables are chosen, the display will alternate between the two with an interval of 3
seconds.
The liquid crystal display includes a field with 4 ½ numeric digits, a field with 5 alphanumeric
digits and an information field, as shown on Figure 2.4.
When the total is displayed, the significant most part appears in the unit and function field
(upper) and the least significant part in the variable field (lower). See Totalization in Section 3.
DISPLAY V6.00
The display controller, from release V6.00 on, is integral to the main board. Please
observe the new spare parts codes.
Monitoring
During normal operation, the LD301 is in the monitoring mode. In this mode, indication
alternates between the primary and secondary variable as configured by the user. See Figure.
2.5. The display indicates engineering units, values and parameters simultaneously with most
status indicators.
The monitoring mode is interrupted when the user does complete local adjustment.
The display is also capable of displaying an error and other messages (See table 2.1).
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