Allen-Bradley MicroLogix 1200 Reference Manual

Publication 1762-RM001C-EN-P
Process Control Instruction 19-13
PLC 5 Gain Range (RG)
When set (1), the reset (TI) and gain range enhancement bit (RG) causes
the reset minute/repeat value and the gain multiplier (KC) to be divided
by a factor of 10. That means a reset multiplier of 0.01 and a gain
multiplier of 0.01.
When clear (0), this bit allows the reset minutes/repeat value and the gain
multiplier value to be evaluated with a reset multiplier of 0.1 and a gain
multiplier of 0.1.
Example with the RG bit set: The reset term (TI) of 1 indicates that the
integral value of 0.01 minutes/repeat (0.6 seconds/repeat) is applied to
the PID integral algorithm. The gain value (KC) of 1 indicates that the
error is multiplied by 0.01 and applied to the PID algorithm.
Example with the RG bit clear: The reset term (TI) of 1 indicates that the
integral value of 0.1 minutes/repeat (6.0 seconds/repeat) is applied to the
PID integral algorithm. The gain value (KC) of 1 indicates that the error is
multiplied by 0.1 and applied to the PID algorithm.
Setpoint Scaling (SC)
The SC bit is cleared when setpoint scaling values are specified.
Loop Update Too Fast (TF)
The TF bit is set by the PID algorithm if the loop update time specified
cannot be achieved by the controller due to scan time limitations.
If this bit is set, correct the problem by updating your PID loop at a
slower rate or move the PID instruction to an STI interrupt routine. Reset
and rate gains will be in error if the instruction operates with this bit set.
Tuning Parameter
Descriptions
Address Data Format Range Type User Program
Access
RG - PLC 5 Gain Range PD10:0/RG binary (bit) 0 or 1 control read/write
NOTE
The rate multiplier (TD) is not affected by this selection.
Tuning Parameter
Descriptions
Address Data Format Range Type User Program
Access
SC - Setpoint Scaling PD10:0/SC binary (bit) 0 or 1 control read/write
Tuning Parameter
Descriptions
Address Data Format Range Type User Program
Access
TF - Loop Update Too
Fast
PD10:0/TF binary (bit) 0 or 1 status read/write

Allen-Bradley MicroLogix 1200 Specifications

General

Series	MicroLogix 1200
Type	Programmable Logic Controller (PLC)
Mounting	DIN rail or panel mount
Programming Language	Ladder Logic
Programming Software	RSLogix 500
I/O Points	Up to 40
Communication Ports	RS-232, RS-485
Memory	6 KB user memory
Power Supply	24V DC or 120/240V AC
Expansion	Supports expansion I/O modules
Operating Temperature	0°C to 55°C (32°F to 131°F)
Dimensions	90 mm x 110 mm
Weight	0.5 kg (1.1 lbs)