Azbil C7G User Manual

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Chapter 4. Functions
Handling Precautions
• Execute MFB AT (MFB auto-tuning) when using settings 0 and 1.
• Accurately set "Full opening time" when using settings 2 and 3.
• Factors that tend to result in the Estimating MFB status when using setting
0 include improper MFB adjustment, deterioration of the motor feedback
potentiometer, poor resolution, and improper MFB input wiring connections.
• While the status is Estimating MFB, the error between the actual MFB
degree of opening and the estimated MFB opening is corrected by turning
ON the CLOSE-side relay when output (MV) ≤ 0.0 % and turning ON the
OPEN-side relay when output (MV) ≥ 100.0 %. The relay turns ON under
these circumstances regardless of the dead zone. For this reason, if the
output changes near 0.0 % or 100.0 % in an oscillating manner, relay ON/
OFF chattering can occur. Some effective methods of preventing chattering
include setting the parameter output low limit (OL) of the PID bank to −1.0 %
or lower, setting the output low limit (OH) to 101.0 % or higher, or setting the
derivative time (D) to 0.0 seconds.

MFB AT (MFB auto-tuning)
The setting is valid if a MOTOR block is inserted (using four slots) into the I/O slot.
MFB AT start and stop can be operated for "Fully closed MFB count," "Fully open
MFB count," or "Full opening time." The settings cannot be configured using the
SLP-C7 Smart Loader Package.
Item (bank) Display Description Initial value
Auto-tuning
PP (position proportional) bank
MENU > PP
Auto-tuning
0: Auto-tuning stop
1: Auto-tuning start
2: Auto-tuning not implemented
3: Auto-tuning completed
4: Auto-tuning failed
2
• MFB AT conditions
MFB AT can be executed when all of the following conditions are satisfied.
•
A valid output is set for "Output type."
•
"Control method selection" is set to 0 (MFB control + estimated position
control) or 1 (MFB control + close upon line break).
•
MOTOR block MFB input and motor drive output are wired correctly.
•
Motor power is turned on, and the motor can be rotated.
• MFB AT method
(1) Setting "Auto-tuning" to 1 (auto-tuning start) starts MFB AT. First, the
CLOSE-side relay turns on, and once the motor rotates and stops in the fully-
closed position, the OPEN-side relay turns on. MFB AT ends when the motor
rotates up to the fully open position.

Azbil C7G Specifications

General

Brand	Azbil
Model	C7G
Category	Controller
Language	English