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VFD Communication Configuration: A Protocol-by-Protocol Guide for Modbus, EtherNet/IP, PROFIBUS & PROFINET
VFD communication configuration is the process of wiring, addressing, and parameterizing a variable frequency drive so a PLC, HMI, or SCADA system can send run commands, speed references, and read status data back. Without it, the drive is an isolated power device; with it, the drive becomes a fully integrated part of an automated control system.
You have already set the motor nameplate data, tuned the V/f curve, and adjusted the ramp settings. But the VFD still sits silent on the plant floor if the communication link is wrong. In a typical water treatment project outside Jakarta, a technician named Andi wired 12 pump VFDs onto a single RS-485 bus. Eleven drives answered immediately. The twelfth dropped offline every few minutes. The fix was not a faulty drive; it was a missing 120 ohm termination resistor at the far end of the bus and a shield grounded at both ends instead of one.
In this guide, you will learn VFD communication configuration from the ground up. We will cover the most common VFD communication protocols used for VFD PLC integration and VFD SCADA communication: Modbus RTU, Modbus TCP/IP, EtherNet/IP, PROFIBUS, PROFINET, and a brief look at CANopen and DeviceNet. You will also get a cross-manufacturer parameter cheat sheet and a practical VFD RS-485 wiring guide you can use on the next commissioning job.
Key Takeaways
- Modbus RTU over RS-485 is the most common starting protocol for VFDs, and it requires daisy-chain wiring, 120 ohm termination at both ends, correct D+/D- polarity, and a single-point shield ground.
- Modbus TCP/IP, EtherNet/IP, and PROFINET use standard Ethernet cabling and IP planning, but each needs its own device description file and tag-mapping convention.
- PROFIBUS remains common in Siemens and ABB systems and uses GSD files with PPO telegrams to exchange control words, status words, and parameter data.
- Every protocol needs the same logical mapping: a control word for start/stop/direction, a frequency reference for speed, and a status word plus feedback registers for current, voltage, output frequency, and fault codes.
- Cross-manufacturer parameter numbers differ, but the functions are the same: select the protocol, set the address, match baud/parity/IP settings, choose the command source, and configure the communication timeout action.
What Is VFD Communication Configuration?
A VFD can run from its own keypad, local input/output terminals, or a networked controller. VFD communication configuration is the work that makes the third option possible. It covers the physical layer, the data-link settings, the application-layer register mapping, and the drive parameters that tell the VFD to accept commands from the network instead of the keypad or terminals.
The physical layer is either a serial bus, usually RS-485 for Modbus RTU, or an Ethernet network for Modbus TCP/IP, EtherNet/IP, PROFINET, and sometimes CANopen over Ethernet. PROFIBUS uses RS-485 physical signaling with its own PROFIBUS protocol on top. DeviceNet and classic CANopen use a Controller Area Network physical layer.
Most VFDs are slaves on the network. The PLC or SCADA system is the master. The master writes to output registers to start the drive and set speed. It reads input registers to see run status, output frequency, current, voltage, and active fault codes. Some protocols also allow the master to read or write any drive parameter while the drive is running.
If you are new to VFD setup, the broader commissioning flow is explained in our VFD configuration guide. That article covers motor data entry, control modes, ramps, and protection parameters before you hand control over to a network.
How to Choose the Right VFD Communication Protocol
The protocol you choose depends on the PLC or SCADA platform already in the plant, the number of drives, the required speed of data updates, the physical distance, and the available budget. The table below summarizes the most common choices.
| Protocol | Best For | Max Distance | Max Nodes | Typical Cable | Termination / Topology |
|---|---|---|---|---|---|
| Modbus RTU | Legacy PLCs, simple serial networks, cost-sensitive projects | 1,200 m at low baud | 32 per segment, 247 with repeaters | Twisted-pair shielded RS-485 | Daisy-chain, 120 ohm at both ends |
| Modbus TCP/IP | Modern Ethernet PLCs and HMIs, easy IP-based networks | 100 m per segment, extend with switches | Limited by IP subnet | Cat5e/Cat6 Ethernet | Star via Ethernet switch |
| EtherNet/IP | Allen-Bradley / Rockwell ecosystems, high-speed control | 100 m per segment | Limited by IP subnet | Cat5e/Cat6 Ethernet | Star or ring with managed switches |
| PROFIBUS DP | Siemens, ABB, and older European automation systems | 1,200 m at low baud | 126 stations | PROFIBUS DP cable (violet) | Daisy-chain, active termination at both ends |
| PROFINET | Siemens S7-1200/1500, modern Ethernet-based plants | 100 m per segment | Limited by IP subnet | Cat5e/Cat6 Ethernet, optional PROFINET cable | Star, line, or ring with PROFINET switches |
| CANopen / DeviceNet | Embedded machinery, older OEM equipment | 40 m at 1 Mbps, 1 km at 50 kbps | 127 nodes | Shielded twisted-pair CAN bus | Daisy-chain, 120 ohm at both ends |
When to Use Modbus RTU
Modbus RTU is the simplest and most widely supported protocol for VFDs. Almost every drive has an RS-485 port, and almost every PLC has a Modbus master instruction. It is the right choice when the PLC is older, the wiring distance is long, the node count is moderate, and the update rate of 100 to 1,000 milliseconds is acceptable.
When to Use Modbus TCP/IP
Modbus TCP/IP uses the same register model as Modbus RTU but runs over Ethernet. It is a good choice when the plant already has an Ethernet infrastructure, when the PLC has an Ethernet port, and when you want to avoid the termination and distance limits of RS-485. IP addressing and subnet planning become the main concerns instead.
When to Use EtherNet/IP
EtherNet/IP is common in North American plants built around Allen-Bradley ControlLogix or CompactLogix controllers. It uses producer-consumer messaging, EDS files, and assembly instances. Choose EtherNet/IP when the control system is Rockwell-based and you need deterministic cyclic data at 10 to 100 millisecond update rates.
When to Use PROFIBUS or PROFINET
PROFIBUS DP is still common in older Siemens S7-300/400 systems and many ABB drives. PROFINET is the modern Ethernet replacement and is the natural choice for Siemens S7-1200/1500 systems. Choose PROFIBUS if the plant standard demands it or if the hardware is already installed. Choose PROFINET for new greenfield Ethernet projects.
When to Use CANopen or DeviceNet
CANopen and DeviceNet are less common in general process plants today, but they still appear in OEM machinery, conveyors, and compact systems. Use them when the machine builder standardized on CAN bus and the VFD is part of a tightly integrated machine control system.
VFD Communication Configuration Workflow
Every VFD communication configuration workflow follows the same logical path. The details change by protocol, but the sequence stays the same. Use these ten steps as your commissioning checklist for VFD PLC integration and VFD SCADA communication projects.
- Identify the PLC or SCADA protocol. Confirm that the VFD supports it, either natively or with an option card.
- Install the correct communication option card if the base drive does not have the required port.
- Wire the physical bus. Use the right cable, topology, and termination for the protocol.
- Set the VFD address. This may be a Modbus slave address, a PROFIBUS station address, an IP address, or a PROFINET device name.
- Match the communication settings. For serial protocols, set baud rate, data bits, parity, and stop bits. For Ethernet protocols, set IP address, subnet mask, gateway, and device name.
- Enable the communication command and frequency sources. Tell the VFD to accept run commands and speed references from the network.
- Map the control word, frequency reference, status word, and feedback registers into the PLC or SCADA tag database.
- Configure the communication timeout and fault action. Decide what the drive does if the network stops talking.
- Test basic read and write commands. Read output frequency and write a small speed reference before issuing a start command.
- Commission the full SCADA database and verify alarms. Confirm that every tag updates correctly and that the drive responds safely to a communication loss.
For example, a technician commissioning a small water treatment plant can complete steps one through seven in an afternoon and have the SCADA tags updating by the end of the day. The real test is step ten: pulling the network cable and confirming the drive coasts to a stop instead of running away.
For a deeper explanation of the parameters that commonly cause trips during this process, see our guide to VFD parameter settings that cause faults.
Modbus VFD Configuration: Modbus RTU and RS-485
Modbus VFD configuration is the most common starting point for technicians. Modbus RTU runs over RS-485 and is supported by nearly every VFD and PLC. It is simple, but small mistakes in wiring or addressing cause big headaches.
VFD RS-485 Wiring: Daisy-Chain, Termination, and Polarity
RS-485 wiring must be a daisy chain, not a star. Run the cable from the PLC or HMI master to VFD 1, then from VFD 1 to VFD 2, and continue to the last drive. Place a 120 ohm termination resistor across the D+ and D- terminals at both ends of the bus. The master end often has the termination built into the PLC port; verify this in the PLC manual. Omitting termination causes signal reflections and intermittent replies, especially on longer buses.
Keep the shield grounded at one point only, usually at the master or at one end of the cable. Grounding the shield at both ends creates ground loops and noise. Route the communication cable away from motor power cables, and never run it in the same conduit as the VFD output power cable.
Polarity matters. Most drives label the terminals D+ and D-, or A and B. The master D+ must connect to all slave D+ terminals, and D- must connect to all slave D- terminals. If the polarity is reversed on one drive, that drive will not respond even though the rest of the bus works.
VFD Modbus Parameter Settings
After wiring, set these parameters in the VFD for a basic Modbus VFD configuration. The exact parameter numbers differ by brand, but the functions are universal.
| Function | Typical Setting | Notes |
|---|---|---|
| Protocol selection | Modbus RTU | Some drives call this “communication protocol” or “fieldbus selection.” |
| Slave address | 1 to 247 | Each drive on the bus must have a unique address. |
| Baud rate | 9600 or 19200 | Must match the PLC master. |
| Data bits | 8 | Standard for Modbus RTU. |
| Parity | None / Even | Must match the PLC master. |
| Stop bits | 1 or 2 | Determined by parity choice; match the master. |
| Command source | Communication / RS-485 | Tells the drive to accept run/stop from Modbus. |
| Frequency source | Communication / RS-485 | Tells the drive to accept speed reference from Modbus. |
| Communication timeout | 2.0 to 5.0 s | Sets the time before the drive declares a fault or coasts. |
| Timeout action | Coast / Fault / Hold last | Choose based on safety requirements. |
Common Modbus Register Map
The exact register addresses vary by manufacturer, but the structure below is representative of many drives. Always verify the register map in the drive manual.
| Register | Typical Address | Data Type | Description |
|---|---|---|---|
| Control word | 40001 or 40009 | 16-bit unsigned | Start, stop, direction, fault reset bits |
| Frequency reference | 40002 or 40010 | 16-bit signed or unsigned | Speed reference, often in 0.01 Hz units |
| Status word | 40011 or 40101 | 16-bit unsigned | Running, fault, direction, ready bits |
| Output frequency | 40012 or 40102 | 16-bit signed | Actual output frequency |
| Output current | 40013 or 40103 | 16-bit unsigned | Output current in 0.1 A units |
| DC bus voltage | 40014 or 40104 | 16-bit unsigned | DC bus voltage in 1 V units |
| Fault code | 40015 or 40105 | 16-bit unsigned | Active fault or last fault code |
The control word usually has bit 0 as the run command, bit 1 as reverse or jog, bit 2 as fault reset, and bit 3 as emergency stop. The status word usually has bit 0 as running, bit 1 as reverse running, bit 2 as fault, and bit 3 as ready.
Example PLC Read/Write Function Codes
A PLC typically uses Modbus function code 03 to read holding registers, function code 06 to write a single register, and function code 16 to write multiple registers. To start the drive, the PLC might write 0x0001 to the control word register and 0x1770, which is 60.00 Hz in 0.01 Hz units, to the frequency reference register using function code 16.
Field Story: The Last Drive on the Bus
Andi, the technician in Jakarta, had eleven VFDs responding perfectly. The twelfth drive replied only when the plant was quiet and went silent whenever a nearby conveyor started. He checked the address, the baud rate, and the polarity twice. Everything matched. Then he noticed the final drive was at the end of a long spur cable rather than the main daisy chain, and the termination resistor was missing. After moving the drive onto the main bus and adding the 120 ohm resistor at the far end, all twelve pumps communicated reliably.
Modbus TCP/IP VFD Configuration
A VFD Modbus TCP/IP configuration uses the same register model as Modbus RTU but wraps it in an Ethernet packet. The main differences are in wiring and IP addressing.
Ethernet Wiring and IP Planning
Connect the VFD to the plant Ethernet switch using Cat5e or Cat6 cable. Assign a static IP address to the drive, or enable DHCP if your network supports it. For industrial control, static IP addresses are preferred so the PLC always finds the drive at the same address after a power cycle.
Plan the IP addresses carefully. Put the PLC, HMIs, drives, and SCADA server on the same subnet if possible. If they must cross subnets, configure the gateway address correctly and ensure the routing rules allow Modbus TCP traffic on port 502.
Register Mapping Differences from Modbus RTU
In Modbus TCP/IP, the register addresses are usually identical to Modbus RTU, but the addressing may be shown as 4x references, 40,001-style references, or zero-based offsets depending on the HMI or SCADA package. A register that is 40001 in Modbus RTU might appear as address 0 or address 40000 in the SCADA tag. Always check the addressing mode setting in your SCADA software.
Example HMI/SCADA Tag Configuration
In an HMI package, create a tag for the VFD IP address, a remote device ID, and the register address. For example, a tag named Pump01_Speed might point to device 192.168.1.21, register 40002, data type 16-bit integer, with a scaling of 0.01 Hz. The same tag can then be bound to a numeric display and a setpoint entry field.
EtherNet/IP VFD Configuration
EtherNet/IP is common in Rockwell Automation systems. It uses a different object model than Modbus and requires an EDS file for easy configuration.
EDS File Import and Device Configuration
Start by obtaining the EDS file from the VFD manufacturer. Install it in RSLogix 5000, Studio 5000, or your PLC programming software. Then add the VFD to the I/O tree. The EDS file tells the PLC what assembly instances, data types, and configuration parameters the drive supports.
Assembly Instances and Instance Attributes
EtherNet/IP exchanges data through assembly instances. The output assembly from the PLC to the VFD usually contains the control word and speed reference. The input assembly from the VFD to the PLC usually contains the status word, output frequency, output current, and fault code. The exact instance numbers, such as 100 for output and 101 for input, are defined by the manufacturer and documented in the EDS file or user manual.
IP Settings and Network Topology
Assign a static IP address to the VFD, or use DHCP with a reservation. In Studio 5000, set the module properties to match the drive IP address and chassis size. EtherNet/IP supports star, linear, and Device Level Ring topologies. For critical applications, a Device Level Ring provides redundancy.
PLC Integration Example
In a CompactLogix system, the VFD appears as an I/O module. The programmer maps the output assembly to controller tags like VFD01_Control and VFD01_SpeedRef, and maps the input assembly to VFD01_Status and VFD01_OutputFreq. The ladder logic then writes to those tags to start and speed-control the drive, and reads the tags to monitor operation.
PROFIBUS VFD Configuration
PROFIBUS DP has been the standard serial fieldbus in many Siemens and ABB plants for decades. A solid PROFIBUS VFD configuration starts with the right GSD file to describe the drive to the master.
GSD File and PPO Telegram Types
Install the GSD file in the PLC configuration software, such as STEP 7 or TIA Portal. The GSD file defines the PPO telegram types. PPO stands for Parameter Process data Object. PPO types 1 through 6 define how many process data words and parameter channel words are exchanged cyclically.
| PPO Type | Process Data Words (PZD) | Parameter Channel Words (PKW) | Typical Use |
|---|---|---|---|
| PPO 1 | 2 | 4 | Basic speed control plus parameter access |
| PPO 2 | 4 | 4 | More process data, such as torque or current |
| PPO 3 | 2 | 0 | Speed control only, no parameter channel |
| PPO 4 | 4 | 0 | More process data, no parameter channel |
| PPO 5 | 8 | 4 | Large process data plus parameter access |
| PPO 6 | 8 | 0 | Large process data, no parameter access |
PPO 1 is the most common starting choice. It provides two process data words for control word and speed reference, plus a parameter channel for reading and writing drive parameters while running.
Station Address, Baud Rate, and Bus Termination
Set the PROFIBUS station address on the drive using rotary switches or parameters. The address must be unique on the bus. PROFIBUS DP automatically detects the baud rate from the master, up to 12 Mbps. Use PROFIBUS DP cable, often violet, and install active bus terminators at both ends of the daisy chain.
Mapping the Control Word and Status Word
In PPO 1, the first process data output word from the PLC is the control word, and the second is the speed reference. The first input word from the drive is the status word, and the second is the actual speed or output frequency. The bit definitions for the control and status words are manufacturer-specific but follow similar conventions to Modbus.
Parameter Channel for Reading and Writing Parameters
The PKW channel allows the PLC to read or write any drive parameter by parameter number and index. This is useful for uploading or downloading parameter sets, changing ramps, or adjusting limits from the PLC program.
PROFINET VFD Configuration
PROFINET is the Ethernet-based successor to PROFIBUS and is now the default choice for new Siemens installations. A PROFINET VFD configuration follows the same idea as PROFIBUS but uses Ethernet and XML-based device description files.
GSDML File and TIA Portal Integration
Download the GSDML file from the VFD manufacturer. In TIA Portal, install the GSDML file, drag the drive into the network view, and assign it to the PLC. PROFINET uses XML-based device description files and supports automatic device replacement if the spare drive has the same device name.
Device Name, IP Address, and Topology
Assign a meaningful device name, such as VFD_Pump01, and either a static IP address or an IP address assigned by the PLC. PROFINET allows you to define the network topology in TIA Portal, including which port connects to which device. If the actual wiring does not match the configured topology, the PLC will flag a diagnostic error.
Cyclic IO vs. Acyclic Parameter Access
Cyclic IO is the real-time exchange of control word, speed reference, status word, and feedback. Acyclic access is used to read or write parameters on demand, such as during commissioning or recipe changes. The cyclic data is mapped in the device configuration, while acyclic requests are made through system function blocks like RDREC and WRREC.
Siemens S7-1200 Example
In a small water boosting station, an S7-1200 PLC controls three pump VFDs over PROFINET. The PLC sends a control word and a speed setpoint to each drive every 4 milliseconds and reads back status, output frequency, and current. The HMI displays the data through the PLC tags, and the SCADA system logs it for energy reporting.
CANopen and DeviceNet VFD Configuration
CANopen and DeviceNet are less common in new process plants, but they still appear in OEM machines and compact control systems.
Node ID and Baud Rate
Set the node ID on the drive using rotary switches or parameters. The node ID must be unique on the CAN bus. Set the baud rate to match the master; common values are 125 kbps, 250 kbps, and 500 kbps. The maximum bus length decreases as the baud rate increases.
PDO vs. SDO Mapping
CANopen uses Process Data Objects for fast cyclic data, such as control word and speed reference, and Service Data Objects for slower parameter access. DeviceNet uses a similar producer-consumer model with explicit and implicit messaging. Mapping the PDOs is the most important step for real-time motor control.
When These Protocols Are Still Used
Choose CANopen or DeviceNet when the machine builder standardized on CAN bus, when space and wiring simplicity matter, or when the VFD is part of a compact embedded system with a CAN-based controller.
Cross-Manufacturer Parameter Cheat Sheet
The table below shows the parameter functions you must set for VFD communication configuration. The parameter numbers vary by manufacturer, so treat this as a starting point and confirm with the drive manual.
| Function | Delta | LS (iG5A) | INVT (GD20) | Mitsubishi (FR-E700) | ABB (ACS580) |
|---|---|---|---|---|---|
| Protocol select | Pr.09-00 | H93 | P00.01 | Pr. 549 | Parameter 58.01 |
| Slave address / node ID | Pr.09-01 | H94 | P00.02 | Pr. 117 | Parameter 58.02 |
| Baud rate | Pr.09-02 | H95 | P00.03 | Pr. 118 | Parameter 58.03 |
| Data / parity / stop bits | Pr.09-03 | H96 | P00.04 | Pr. 119 | Parameter 58.04 |
| Frequency command source | Pr.02-00 | H40 | P00.06 | Pr. 79 | Parameter 20.01 |
| Run command source | Pr.02-01 | H41 | P00.07 | Pr. 79 | Parameter 20.02 |
| Communication timeout | Pr.09-04 | H98 | P00.09 | Pr. 122 | Parameter 58.14 |
| Timeout action | Pr.09-05 | H99 | P00.10 | Pr. 122 | Parameter 58.15 |
| Frequency reference register | 40002 | 40002 | 40002 | 40014 | Reference speed word |
| Control word register | 40001 | 40001 | 40001 | 40009 | Control word word |
This table is a general reference. Parameter numbering and register addresses change between product generations and firmware versions. Always verify against the latest drive manual before commissioning.
Common VFD Communication Configuration Mistakes
Most VFD communication configuration failures come from a short list of setup errors. Checking these items first will save hours of troubleshooting.
- Missing or wrong termination. RS-485 and PROFIBUS buses need 120 ohm termination at both ends. Spur cables and star topologies cause reflections.
- Reversed RS-485 polarity. D+ and D- must maintain the same polarity from the master through every slave.
- Duplicate slave addresses. Two drives with the same address will both try to reply, corrupting the bus.
- Mismatched baud, parity, or stop bits. Every device on a serial bus must use identical settings.
- Missing communication timeout action. If the PLC stops communicating and the drive keeps running at the last speed, safety can be compromised.
- Shield grounded at both ends. This creates ground loops and noise. Ground the shield at one end only.
- Ethernet IP conflict. Two devices with the same IP address will both drop offline intermittently.
- Wrong control word bit definitions. Not every drive uses the same bit layout. Verify the manufacturer mapping before writing start commands.
- Ignoring drive faults. A communication error can mask an underlying VFD overcurrent fault or VFD overvoltage fault. Check the drive keypad before blaming the network.
If you hit a fault during commissioning, our VFD communication fault troubleshooting guide walks through the most common serial and Ethernet errors step by step.
VFD Communication Configuration: FAQ
What cable do I use for VFD Modbus RTU?
Use a shielded twisted-pair cable rated for RS-485. A typical choice is 24 AWG or 22 AWG with a foil or braid shield. The characteristic impedance should be around 120 ohms to match the termination resistors.
Can I run VFD communication and power in the same conduit?
No. The high-frequency switching noise from VFD output power cables couples into the communication cable and causes data errors. Run communication cables in a separate conduit or cable tray, and keep them at least 30 centimeters away from power cables.
What is the default Modbus address for most VFDs?
Many drives ship with a default Modbus address of 1. Some use 0 or 2. Never assume the default. Set each drive to a unique address before connecting it to the bus.
How do I read VFD output frequency from a Modbus register?
Use Modbus function code 03 to read the holding register assigned to output frequency. The address is usually in the 40011 to 40110 range depending on the manufacturer. The value is often scaled, such as 0.01 Hz per count.
Why does my VFD drop offline after the last drive on the RS-485 bus?
The last drive is at the end of the line and sees the worst reflections if termination is missing or if the cable forms a star or spur. Add a 120 ohm termination resistor across the D+ and D- terminals at the far end of the bus.
Do I need an option card for EtherNet/IP or PROFINET?
Many modern VFDs offer built-in Ethernet ports, but some require a communication option card. Check the drive model and order code. A drive without an Ethernet port cannot be upgraded by parameter settings alone.
Can I control multiple VFDs from one PLC Modbus port?
Yes. A single RS-485 Modbus master port can control up to 32 drives per segment without repeaters, and up to 247 with repeaters. Each drive must have a unique slave address.
What is the difference between PPO 1 and PPO 6 in PROFIBUS?
PPO 1 has two process data words plus a four-word parameter channel. PPO 6 has eight process data words but no parameter channel. Use PPO 1 when you need to read or write drive parameters over PROFIBUS. Use PPO 6 when you need more real-time process data.
Quick Reference: VFD Communication Protocol Selection
Use the checklist below to choose a protocol for your next project.
| Question | Choose Modbus RTU | Choose Modbus TCP/IP | Choose EtherNet/IP | Choose PROFIBUS | Choose PROFINET |
|---|---|---|---|---|---|
| PLC is older or serial only | Yes | No | No | Maybe | No |
| Long distance, low cost | Yes | No | No | Yes | No |
| Modern Ethernet PLC | Maybe | Yes | Yes | No | Yes |
| Rockwell control system | No | Maybe | Yes | No | No |
| Siemens control system | No | Maybe | No | Yes | Yes |
| Need simple register access | Yes | Yes | No | Yes | Yes |
| Need high-speed cyclic control | No | Maybe | Yes | Yes | Yes |
Conclusion
VFD communication configuration turns a stand-alone drive into a networked automation device. The protocol you choose depends on the PLC, the plant infrastructure, and the performance you need, but the configuration workflow is the same: wire the bus, set the address, match the communication settings, map the control and feedback registers, and verify the timeout behavior.
Start with Modbus RTU when the project is simple and serial. Move to Modbus TCP/IP or EtherNet/IP when the plant is Ethernet-based. Choose PROFIBUS for legacy Siemens or ABB systems, and PROFINET for new Siemens projects. Pay attention to termination, polarity, shield grounding, and unique addresses, and most commissioning jobs will go smoothly.
For applications such as pump stations or HVAC plants, communication is often the link between the drive and the central SCADA system. If your next step is to add closed-loop pressure control, see our guide to VFD PID control. And if you need help selecting the right drive size and communication options for your motor, our team can assist with how to size a VFD for a motor.
Need application support or a VFD with the right communication interface for your PLC? Contact our engineering team to discuss your project requirements.
