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Operation and Maintenance
February 2019
Stop Bits: This setting determines the number (1 or 2) of stop bits used when ending a
message. This setting is only required for Modbus RTU.
Response delay time (ms): This setting determines how long (ms) the Gateway waits
before responding to a Modbus request. This setting is only required for Modbus RTU.
Unmapped register read response?: This is the value returned by the Gateway if the
Modbus master requests a register with no data assigned to it (empty register). It is
recommended this be set to zero fill to prevent errors.
Floating point representation: This setting determines if the Gateway uses floating point
values or integer values. There are three options for this setting.
•
Float–uses 32 bit floating point values
•
Round–rounds the data value to the nearest whole number
•
Scaled–uses scaled integers to offset negative values or increase decimal point
resolution. The equation for scaled integers is:
y = Ax - (B - 32768)
Where:
y = Scaled integer returned by the Gateway
A = Gain for scaled integer value
x = Measured value from wireless field device
B = Offset for scaled integer value
Use swapped floating point format?: This setting switches which register is sent first for a
floating point value. This setting is only used for floating point values.
Incorporate value's associated status as error?: This setting causes the Gateway to report a
predetermined value when a communications or critical diagnostic error is received from
the wireless field device. The value is user configurable depending on which floating point
representation is chosen. See Value reported for error below.
Value reported for error (floating point): This setting determines what value is reported if
the wireless field device reports a failure or stops communicating to the Gateway. This
setting is used for floating point values. The choices are NaN (not a number), +Inf (positive
infinity), -Inf (negative infinity), or Other (user specified).
Value reported for error (rounded and native integer): This setting determines what value
is reported if the wireless field device reports a failure or stops communicating to the
Gateway. This setting is used for rounded or scaled integers. The choice is a user specified
value between -32768 and 65535.
Scaled floating point maximum integer value: This determines the maximum integer value
for the purpose scaling integers. 999-65534
Use global scale gain and offset?: This setting determines if a global gain and offset is
applied for scaled integers or if each value has a unique gain and offset. Unique gain and
offsets are found on the Modbus Mapping page.
Global scale gain: This value is multiplied by the data values for the purpose of scaling
integers. If global scaling is not selected, a gain value will be available for each separate
data value on the Modbus Mapping page.
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Reference Manual
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