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MOTOR_REV Logic Block Documentation

Overview

The MOTOR_REV function block is designed to control motors that require both forward and reverse operations. It facilitates the safe starting, stopping, direction switching, and health monitoring of motors within an industrial automation environment.

This block is essential for machinery where direction control is required, such as conveyors, hoists, or certain types of pumps.

Logic Block Illustration

The MOTOR_REV block provides:

  • Bidirectional Motor Control: Supports start/stop logic for both forward and reverse operation.
  • Auto/Manual Mode Handling: Enables switching between automatic and manual control modes.
  • Safety and Permissive Checks: Executes interlock and permissive logic separately for forward and reverse directions.
  • Feedback Monitoring: Monitors run feedbacks for both directions and uses timers to detect abnormal conditions.
  • Runtime Monitoring: Tracks motor run hours and provides hardware interface signals for diagnostics.

../../Images/Programing_Manual/Logic_Manual/MOTOR_REV/Bl_motor_rev2.png

Showing the MOTOR block in the above picture.

../../Images/Programing_Manual/Logic_Manual/MOTOR_REV/MOTOR_REV_1.png

The above picture shows how the inputs and outputs are connected in the MOTOR block.

Input and Output Parameters

Signal Type Description
ioRFB_FWD BIT Motor forward run feedback signal
ioRFB_REV BIT Motor reverse run feedback signal
ioTrip BOOL Motor trip feedback (fault detected)
intl BIT Interlock condition (shared)
perm_FWD BIT Permissive condition for forward operation
perm_REV BIT Permissive condition for reverse operation
Auto_FWD BIT Automatic command for forward operation
Auto_REV BIT Automatic command for reverse operation
Auto_STOP BIT Automatic stop command
CycleTime BIT Cycle time signal for closed loop control
Start_FWD BIT HMI start command for forward direction
Start_REV BIT HMI start command for reverse direction
Stop BIT HMI stop command
ioFWD_CMD BIT Forward run command output
ioREV_CMD BIT Reverse run command output
Run_fb_Timer REAL Wait time for receiving run feedback after command
Mode BOOL FALSE = Manual, TRUE = Auto mode selection
HMI_Interface_hardware WORD Interface message code for hardware-related messages on HMI
Run_Time REAL Total motor run time in hours
IntlBypass BIT Interlock bypass switch
PermBypass_FWD BIT Bypass forward permissive
PermBypass_REV BIT Bypass reverse permissive
TagName STRING(10) Tag name identifier for this motor
Desc STRING(12) Description of the motor

Operational Behavior

Auto Mode Behavior

  • In Auto mode (Mode = TRUE):
  • Motor runs forward if Auto_FWD = TRUE, perm_FWD = TRUE, and no interlock.
  • Motor runs reverse if Auto_REV = TRUE, perm_REV = TRUE, and no interlock.
  • If Auto_STOP = TRUE, the motor is stopped.

Manual Mode Behavior

  • In Manual mode (Mode = FALSE):
  • Start_FWD or Start_REV initiates motor operation in respective direction.
  • Stop halts any current motor operation.

Safety Handling

  • The motor runs only when:
  • Interlocks are inactive (intl = FALSE) or bypassed (IntlBypass = TRUE)
  • Direction-specific permissives (perm_FWD or perm_REV) are valid or bypassed

Feedback and Diagnostics

  • If motor does not start after command within Run_fb_Timer, fault is flagged.
  • Interface messages are pushed to HMI via HMI_Interface_hardware for user alerts.

Best Practices

  • Configure Run_fb_Timer appropriately based on your motor's expected startup time.
  • Enable bypass only during commissioning or manual override scenarios.
  • Separate control and HMI logic should monitor ioRFB_FWD and ioRFB_REV to reflect real motor status.
  • Use Desc and TagName to provide clear and descriptive motor identity on HMI.
  • Regularly check Run_Time to monitor wear and schedule preventive maintenance.

Summary

The MOTOR_REV block adds directional intelligence and flexibility to motor control within industrial environments. With support for both manual and automated operations, dual-direction logic, comprehensive safety checks, and HMI diagnostics, it ensures a reliable and operator-friendly motor management strategy.

Designed for high-precision motor applications requiring controlled forward/reverse operations, with built-in safety, feedback, and runtime tracking.