VFD - Variable Frequency Drives

Unitronics VFDs work seamlessly with UniStream, as well as with Vision and Samba controllers.

Communicating via Modbus RTU , they are general purpose VFDs, available as single and three phase, from 0.4 kW up to 110 kW.

You can use UniLogic to configure and operate up to 32 Unitronics VFDs via Ladder, or directly from UniStream's HMI panel.

Once you have configured your VFD, you can run and control it via your PLC and HMI applications.

You can also monitor and debug your VFD remotely by running OnLine Test Mode, and using UniLogics' Scope Trace feature as an oscilliscope.

Communications

Configuring your Serial Port to VFD

UniStream Modular

The VFD can only be connected to the serial port of the CPU, and may not be connected to a COM module.

You can add up to 2 RS485 Serial ports, configure them to VFD, and connect a VFD to each port.

Configuring Ethernet (Modbus TCP) VFDs

Add VFDs

Configuring VFDs

UniLogic - Directly editing the Configuration

The image below shows a Configuration file, which you can edit by clicking in the parameter fields.
In the image, the right side shows groups of parameters. The groups outlined in green are specific to UniLogic:

The groups outlined in red are the standard parameter groups of the VFD model you are using.

VFD Struct

UniLogic uses the VFD struct to contain the Configuration file parameter data, as shown in the next image.

The section of the struct outlined in green contains tags for parameters that are unique to UniLogic and UniStream; the rest of the struct contains tags that link to parameter groups in the VFD configuration file. For example, note the Basic Function Group outlined in red in the next image. The Configuration file contains 19 parameters; the linked UniLogic struct tag is an array of 18 UINT16.

Enabling Communication: UniStream to VFD

To enable UniStream to communicate with the VFD via the parameters in the VFD Configuration file, you must enable the VFD for Modbus communication.
In the P00 Basic Function group, set:

VFD Ladder Functions

Code	Message
0	Success
1	Pending (in Queue)
2	In Progress
-1	Enable Communication Bit is OFF (struct tag IO / InverterName / Enable Communication
-2	Queue Full; retry after current program scan is complete
-3	Enable Communication Bit has been turned OFF while pending requests are in queue (code 1), or requests are in progress (code 2)
-4	Communication Timeout Exceeded
-5	Configuration File Mismatch
-6	Store/Load Configuration Error: File Name does not exist
-7	VFD Write Modified Rebuild and download your project, if the error persists, contact Support
The next two codes, -8 & -9 relate to Read/Write function commands that use indirect addressing. Commands are divided into 30 groups (P00-P29). A command is comprised of the group name, and a command parameter. For example, in the command P08.06, P08 refers to the 'Enhanced Functions' group, and 06 is the parameter 'Jog running ACC time'.
-8	Read/Write, Group Number Error: the Group does not exist
-9	Read/Write, Command Function Error: the parameter does not exist
-10	Fault Message Response: these are communication errors. Check the code in struct tag IO / InverterName / Inverter Status, and refer to inverter manual, section Fault Message Response
-11	Invalid Permission
-12	Unexpected response from inverter
-13	VFD identification in progress. Note that during the identification process, in the VFD struct, the VFD is Connected bit is OFF.
-14	Auto-tune - Mode does not exist
-15	RS485 Network data overload

VFD: Read/Write Direct Ladder Functions

In addition to the functions listed above, you can use Ladder functions to read and write directly to a VFD via Modbus, using the addresses available in the VFD documentation.

Parameter Name	Data Type	Description
Enable Communication	Bit	Turn this ON to allow communications between UniStream and the VFD. It is recommended to use the status of this bit as a condition in your program.
VFD is Connected	Bit	This is ON when the VFD is connected. It is recommended to use the status of this bit as a condition in your program.
When Enable Communication is turned ON, UniStream attempts to establish communications with the VFD and identify whether it is a Unitronics VFD. During this process: Both Enable Communication and VFD is Connected bits are turned OFF. Any VFD functions that require communications will return the VFD Status code -13 Success: the VFD is identified as a Unitronics device. Both Enable Communication and VFD is Connected bits turn ON. Failure 1: the VFD is not a Unitronics device: Both Enable Communication and VFD is Connected bits remain OFF. Enable Communication is switch OFF, VFD is Connected remains OFF. Check the status code of VFD functions that require communications. VFD Status will be -1 Failure 2: VFD Type mismatch (the VFD Type selected in UniLogic is not the actual VFD type that UniStream is attempting to communicate with: Check the status code of VFD functions that require communications. VFD Status will be -2
Enable Periodic Status Read	Bit
Status	UINT32	This must be reset by the user. -1= the VFD is not a Unitronics device -2 =VFD Type mismatch For all other Status codes, refer to the VFD Status codes in the manual.
VFD Status	INT 16	The exception response frame has two fields that differentiate it from a normal response frame: - The exception function code of the exception response is equal to the function code of the original request plus 128 (0x80). - The exception code depends on the communication error that the slave encounters. Exception Code Name Description 01 (0x01) Illegal function The function code received in the request is not an authorized action for the slave. The slave may be in the wrong state to process a specific request. 02 (0x02) Illegal data address The data address received by the slave is not an authorized address for the slave. 03 (0x03) Illegal data value The value in the request data field is not an authorized value for the slave. 04 (0x04) Slave device failure The slave fails to perform a requested action because of an unrecoverable error. 05 (0x05) Acknowledge The slave accepts the request but needs a long time to process it. 06 (0x06) Slave device busy The slave is busy processing another command. The master must send the request once the slave is available. 07 (0x07) Negative acknowledgment The slave cannot perform the programming request sent by the master. 08 (0x08) Memory parity error The slave detects a parity error in the memory when attempting to read extended memory. 10 (0x0A) Gateway path unavailable The gateway is overloaded or not correctly configured. 11 (0x0B) Gateway target device failed to respond The slave is not present on the network.
Current Configuration Name	String-ASCII	The name assigned to the configuration.
VFD Line (Type)	String-ASCII	The type of VFD selected in Hardware Configuration, for example \|UMI-BU-B1
VFD Model	String-ASCII	The VFD model elected in Hardware Configuration,, for example UMI-0004BU-B1
Basic Function Group	UINT16 (0-18)	These relate to the parameter groups in the VFD Configuration. For details, refer to the manual for the specific VFD type. The manuals are located online in the Unitronics Technical Library.
Start- p and Stop Control	UINT16 (0-25)
Motor 1	UINT16 (0-28)
Vector Control	UINT16 (0-26)
V/F control	UINT16 (0-33)
Input Terminals	UINT16 (0-54)
Output Terminals	UINT16 (0-26)
Human-Machine Interface	UINT16 (0-56)
Enhanced Function	UINT16 (0-51)
PID control	UINT16 (0-16)
Simple PLC and multi-stage Speed control	UINT16 (0-37)
Protective parameters	UINT16 (0-16)
Synchronous motor control	UINT16 (0-15)
Status	UINT16 (0-39)

Group	Function Name	Purpose
Configure the VFD	VFD Read Configuration	Reads (uploads) VFD Configuration file data from the VFD device to the VFD Struct
	VFD Write Configuration	Writes all of the data in the VFD struct to the VFD device
	VFD Load Configuration from File	Loads VFD Configuration data from the file specified in the function in UniLogic to the VFD struct
	VFD Store Configuration to File	Stores the last loaded VFD Configuration of the VFD specified, to the Configuration file specified in the function
	Write Modified Parameters	Writes only the VFD data that has been modified to the device and saves the successfully modified values to the struct

Group	Function Name	Purpose
Read / Write Parameters to the VFD	VFD Read Parameter Direct	Read a value from the VFD, directly from the specified parameter
	VFD Read Parameter InDirect	Read a value from the VFD, indirectly, using a tag to store the parameter name (group and index)
	VFD Write Parameter Direct	Write a value from the VFD, directly from the specified parameter
	VFD Write Parameter InDirect	Write a value from the VFD, indirectly, using a tag to store the parameter name(group and index)

Group	Function Name	Purpose
Operate the VFD	VFD Run Frequency Mode	Use this to start running the VFD in Frequency Mode, at the frequency and direction specified in the ladder element.
	VFD Stop VFD	This stops the VFD, at the defined deceleration rate.
	VFD Jog Frequency	Use this to start jogging the VFD, at the frequency and direction specified in the ladder element.
	VFD Stop Jogging	Use this to stop jogging the VFD.
	VFD Run Torque Mode	Starts the VFD in Torque Mode, at the torque and within the limits set in the function To run Torque Mode: P0.00 MUST be set to 0 or 1 P0.311 MUST be set to 7 (Modbus Control) To enable torque limits to be set via keypad or enable the PLC to control torque, use P0.14 and P0.15 (6 = Modbus Control)
	VFD Emergency Stop	Immediately stops the VFD (does not affect inertia) Note: The inverter cannot: Be used as “Emergency-stop device”. Be used to brake the motor suddenly. A mechanical braking device should be provided.
	VFD Fault Reset	Use this to reset the VFD Fault
	VFD AutoTune	Use this to run Autotune on the VFD.

VFD - Unitronics' Variable Frequency Drives