Introduction

This article provides details for the use and application of the Speed Control (DINT) function block. Using this function block with the CJ2M-MD21/MD212 provides an easy means of controlling a servo's speed.

This function block can be of particular use in PLC-based motion control applications often found in packaging machinery. To see a machine case study of a packaging application that controls servos with the CJ2-Series Pulse Output Unit, visit the link below at the packaging solutions area:

industrial.omron.eu/vertical-flow-wrapper

Speed Control (DINT)

Name

Speed Control (DINT): MD_CPU031_MoveVelocity_DINT

Basic Function

Controls speed.

Symbol

Originates from

Tsunagi Lab Europe

Created by

OEE-HQ HvB (creation and testing)

File Name

MD_CPU031_MoveVelocity_DINT.cxf

Applicable models

CPU Unit

CJ2M-CPU Unit version 2.0 or higher with max. two
CJ2M-MD211 (NPN) or
CJ2M-MD212 (PNP)

CX-Programmer

Version 9.1.2 or higher

Conditions for usage

None.

Function Description

Executes speed control for the output specified with the Axis No. (Axis) using the Speed command (Velocity) when Start (Execute) is turned ON.
The Speed reached (InVelocity) will be turned ON once the speed reaches the target speed specified in this FB.

If the speed control is interrupted by a deceleration stop caused by another instance or error, the Speed reached (InVelocity) will be reset.
The Error flag (Error) will be turned ON and Error code (ErrorID) will be output when an error related to this FB occurs.
These statuses, Speed reached (InVelocity)/ Error flag (Error)/ Error code (ErrorID), will be reset when Start (Execute) is turned OFF.

If Start (Execute) was turned OFF before positioning is completed, the status will be set for at least one cycle when a corresponding condition occurs.

Kind of FB definition

Connect Always ON type
  Connect the EN input to the Always ON Flag (P_ON).
  The same instance cannot be used in two or more places.

FB Precautions

• When using the Pulse output 0&1 or 2&3 simultaneously, use the same Pulse output method for them.
• When speed is changed by the other command before the speed reaching, this FB will output an error.
• Turning ON the input to the Start (Execute) during speed control will cause multistart, which then leads to speed control with the speed set in Speed command (Velocity).
• When already in speed control operation, direction specification (sign of the Speed command (Velocity)) will be ignored and only the speed will be changed. To reverse the direction of the operation, stop the operation once and execute the speed command with the opposite direction specified.

The MD_CPU* function blocks are offered 'as is' and may serve as a basis for development. Users should previously test its adequacy to the final application.

Omron can not be held responsible in case of malfunction.

EN input condition

 • Connect the EN input to the Always ON Flag (P_ON).
 • If a different type of bit is connected to EN, the FB outputs will be maintained when the connected bit is turned OFF.

Restrictions other

• During positioning operation, this FB can not be executed.
• During operations by ACC, discrete, commands, this FB cannot be executed during the Origin Search operation.

Application example

Turning the start trigger from OFF to ON will start operating the Servomotor connected to the Pulse output 0 on the CJ2M-MD21* Unit with relative movement.

Related manuals

 CJ2M Pulse I/O User Manual (W486)
 CJ2 Hardware User Manual (W472)

EN

EN

BOOL

1 (ON): Starts FB
0 (OFF): Does not start FB

Axis No.

Axis

INT

&0

&0 to &

&0: Pulse output 0,  &1: Pulse output 1
&2: Pulse output 2,  &3: Pulse output 3

Start

Execute

BOOL

0(OFF)

OFF -> ON (rising edge) starts speed control

Speed command

Velocity

DINT

+0

-100000 to +100000

Specifies the target speed.
Unit: Hz

Acceleration rate

Acceleration

INT

&1

&1 to &65535

Specifies the acceleration rate.
Unit: Hz/4ms (Increase (Hz) in Pulse frequency per Pulse control period (4ms))

Pulse output method

OutPulseSelect

INT

&0

&0 to &1

&0: CW/CCW output
&1: Pulse + direction output

ENO

ENO

BOOL

1 (ON): FB operating normally
0 (OFF): FB not operating normally

Speed reached

InVelocity

BOOL

1 (ON) indicates that the target speed has been reached.

Error flag

Error

BOOL

1 (ON) indicates that an error has occurred in the FB.

Error code (May be omitted)

ErrorID

WORD

The error code of the error occurred in the FB will be output. For details of the errors, refer to the sections of the manual listed in the Related manuals above. When Unit No. or Axis. No. is out of the range, #0000 will be output.