Hardy 1734-WS Installation & Operation Manual
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Parameter RD1
DINT
Parameter RD2
DINT
Total
14
The first four variables in the input table, Command Echo, Command Status, Parameter ID, and Parameter
Value, closely match the first four variables in the output table. The Command Echo is used to echo the
command from the output table, to enable the PLC to ensure that the correct command has been executed;
and also that the command status value is valid.
The Parameter ID; is an echo of the value sent in the output table, while the Parameter Value is the value for
the specified Parameter ID. A 16-bit value, Instrument Status, provides the current state of all the major
functions within the instrument. The top 8 bits are a cyclic “measurement update count”, which will
increment by a count of one every time a new measurement value is taken, following a 0 to 255 then repeat
cycle. If this value remains the same in two consecutive reads from the instrument then the communication
or the measurement function has failed and the appropriate action needs to be taken. The bottom 8-bits
reflect the status of all the major functions and should be used in conjunction with the “measurement update
count” to determine the health of the instrument.
The Net and Gross Weight values are always provided. The final two read only command values Parameter
RD1 Value and Parameter RD2 Value are the read only values for the different user selectable parameter ID
values set in the output table. If a 0x0000 is placed in the Parameter RDx ID value, or the requested
parameter does not exist a 0x0000 value will be returned.
