Publication 1762-RM001C-EN-P
19-6 Process Control Instruction
Output Limit (OL)
An enabled (1) value enables output limiting to the values defined in
PD10:0.CVH (Control Variable High) and PD10.0.CVL (Control Variable
Low).
A disabled (0) value disables OL (Output Limiting).
Control Variable High Limit (CVH)
When the output limit bit (PD10:0/OL) is enabled (1), the CVH (Control
Value High) you enter is the maximum output (in percent) that the control
variable attains. If the calculated CV exceeds the CVH, the CV is set
(overridden) to the CVH value you entered and the upper limit alarm bit
(UL) is set.
When the output limit bit (PD10:0/OL) is disabled (0), the CVH value you
enter determines when the upper limit alarm bit (UL) is set.
If CV exceeds the maximum value, the output is not overridden and the
upper limit alarm bit (UL) is set.
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 Parameter
Descriptions
Address Data
Format
Range Type User Program
Access
OL - Output Limit PD10:0/OL binary 1 = enabled
0 = disabled
control read/write
Output Parameter
Descriptions
Address Data Format Range Type User Program
Access
CVH - Control
Variable High Limit
PD10:0.CVH word (INT) 0 to 100% control read/write
Output Parameter
Descriptions
Address Data
Format
Range Type User Program
Access
CVL - Control
Variable Low Limit
PD10:0.CVL word
(INT)
0 to 100% control read/write