Future Design MCTB 4.3, Руководство пользователя

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MCTB
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The input unit selections for temperature are mutually exclusive, i.e., selecting one will turn off the other. Once
the desired temperature units have been selected, press the “Done” button to set the input units for the loop
control board and return to the main Loop Configuration screen.
4.2.4 Decimal Point
The Decimal Point entry allows the input precision to be adjusted between zero and one decimal digits for
temperature input types, between zero and two for a 0-60mV input and from zero to three for VDC and mA
input types.
IMPORTANT: Once the loop control board has been configured with a specific decimal point, changing the
decimal point will require the loop control board to be reconfigured in order to maintain previous
control settings. Automatic programs, alarm set points, set point limits, input low/high scale,
etc., DO NOT automatically scale. An entry of 100.0 becomes 1000 when changing the
decimal point to zero (not 100) and must be re-entered to set the proper value.
4.2.5 Input Low/High Scale
The Input Low Scale and Input High Scale entries are used to set the input range for linear input types (VDC or
mA). The entries are not available for temperature input types since they utilize a fixed range based on the
sensor type. The input low scale value can be set from -32768 up to the high scale value minus 50. The high
scale value can be set from the low scale value plus 50 up to 32767.
NOTE:
The minimum and maximum scale values are limited by the decimal point selection. For a decimal
of 0, the values are -32768 and 32767 respectively. For one decimal point, the values are -3276.8
and 3276.7. For two decimal digits, the values are -327.68 and 327.67 and for three decimal digits
the values are -32.768 and 37.767.
4.2.6 Input Filter
The Input Filter entry is used to select the time constant used for filtering the process input.
The time constant selections are mutually exclusive, i.e., selecting one will turn off the others. Once the desired
filter constant has been selected, press the “Done” button to set the input filter for the loop control board and
return to the main Loop Configuration screen.