Future Design MCTB 4.3, Руководство пользователя

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MCTB
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The input type selections are mutually exclusive, i.e., selecting one input will turn all other selections off. Once
the desired input type has been selected, press the “Done” button to set the input type for the limit control and
return to the main Limit Configuration screen.
NOTE: The L41 limit control is equipped with DIP switches located on the side of the unit. The DIP switches
must be set properly according to the input type selection made. For temperature (RTD and T/C) and
mV input, DIP switch 1 must be set to on and DIP switch 2 set to off. For a linear voltage input, DIP
switch 1 must be off and DIP switch 2 set to on. For linear mA inputs, both DIP switches 1 and 2
must be set to on.
Input type selections of 0-1V, 0-5V and 1-5V requires a special order L41. Only the 0-10V input
selection is compatible with standard L41 units. If a 0-1V, 0-5 or 1-5V input is required, it must be
ordered accordingly. Linear inputs, current and voltage, are not FM approved.
4.3.3 Input Units
The Input Units entry is used to select the temperature units for temperature input types (thermocouple or RTD).
If the selected input type for the limit is a linear input (VDC or mA), the Input Units entry will display the text
entry keypad allowing the user or OEM to enter specific engineering units up to 4 characters.
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 limit
control and return to the main Limit Configuration screen.
4.3.4 Decimal Point
The Decimal Point entry allows the input precision to be adjusted between 0 and 1 decimal digits for temperature
input types and between 0 and 3 for a 0-60mV input and VDC and mA input types.
IMPORTANT: Once the limit control has been configured with a specific decimal point, changing the decimal
point will require the limit control to be reconfigured in order to maintain previous control
settings. Alarm set points, 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.