Publication 1766-RM001A-EN-P - October 2008
Process Control Instruction
337
Control Variable Low Limit (CVL)
When the output limit bit (PD10:0/OL) is enabled (1), the CVL (Control
Value Low) you enter is the minimum output (in percent) that the Control
Variable attains. If the calculated CV is below the minimum value, the CV
is set (overridden) to the CVL value you entered and the lower limit alarm
bit (LL) is set.
When the output limit bit (PD10:0/OL) is disabled (0), the CVL value you
enter determines when the lower limit alarm bit (LL) is set. If CV is below
the minimum value, the output is not overridden and the lower limit
alarm bit (LL) is set.
Output Parameters
The table below shows the output parameter addresses, data formats, and
types of user program access. See the indicated pages for descriptions of
each parameter.
Control Variable (CV)
The CV (Control Variable) is user-defined. See the ladder rung below.
Output Parameter
Descriptions
Address
Data
Format
Range
Type
User Program
Access
CVL - Control
Variable Low Limit
PD10:0.CVL
word
(INT)
0…100%
control
read/write
Output Parameter Descriptions Address
Data Format Range
Type
User Program
Access
For More
Information
CV - Control Variable
User-defined
word (INT)
0…16,383
control
read/write
CVP - Control Variable Percent
PD10:0.CVP
word (INT)
0…100
control
read/write
SPV - Scaled Process Variable
PD10:0.SPV
word (INT)
0…16383
status
read only
Output Parameter
Descriptions
Address
Data
Format
Range
Type
User Program
Access
CV - Control Variable
User-defined
word (INT) 0…16,383
control
read/write
0000
PID
PID
PID File
PD10:0
Process Variable
N7:0
Control Variable
N7:1
Setup Screen
PID
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