HMIs
Human Machine Interfaces (HMIs) provides a graphical interface for operators to interact with and monitor industrial equipment, such as PLCs, RTUs, IEDs, and other devices. Centro carries a complete selection of HMIs available to purchase online, including HMI software, PLCs, RTUs, IEDs, and more. We offer products from leading manufacturers such as Serial Solutions, GE Intelligent Platforms, Rockwell Automation, and others. Whether you're looking for a simple HMI software package or a full-featured HMI PLC, we have the right solution for your application. Please browse our website today.
$724.18
Subject to factory lead times
$648.30
Subject to factory lead times
$457.15
Subject to factory lead times
$256.57
Subject to factory lead times
$648.30
Subject to factory lead times
$724.18
Subject to factory lead times
$519.02
Subject to factory lead times
$339.60
Subject to factory lead times
$457.15
Subject to factory lead times
$517.47
Subject to factory lead times
$724.18
Subject to factory lead times
$648.30
Subject to factory lead times
$457.15
Subject to factory lead times
$256.57
Subject to factory lead times
$648.30
Subject to factory lead times
$724.18
Subject to factory lead times
$519.02
Subject to factory lead times
$339.60
Subject to factory lead times
$457.15
Subject to factory lead times
$517.47
Subject to factory lead times
- An HMI is a local operator interface — it displays process data and accepts operator input at a single machine or panel. SCADA (Supervisory Control and Data Acquisition) is a broader system architecture that collects data from multiple HMIs, PLCs, and field devices across an entire facility or geographic area, centralizing monitoring, historical data logging, and reporting at a supervisory level. In practice, most modern HMI panels can serve as the local interface while also feeding data upstream to a SCADA server. For single-machine or single-process applications, an HMI alone is typically sufficient.
- Most industrial HMI panels support a range of standard protocols to communicate with PLCs and controllers from various manufacturers. Ethernet-based protocols — EtherNet/IP, Modbus TCP, and PROFINET — are the current standard for new installations. Serial protocols such as Modbus RTU and RS-232/485 remain common for legacy equipment. Many panels also support OPC-UA for seamless integration with SCADA systems and MES platforms. When selecting an HMI, verify that it natively supports the protocol of your PLC or controller without requiring additional gateways or converters.
- A full HMI panel is a self-contained unit with its own processor, memory, and software environment — it runs the HMI application locally and communicates directly with PLCs. A flat panel monitor display is essentially an industrial-grade screen without onboard processing; it requires a separate PC or industrial computer to run the HMI software and simply outputs that image to the display. Flat panel monitors offer flexibility for high-performance or complex visualization applications where a dedicated PC provides more processing power than a standalone HMI. Full HMI panels are the simpler, more cost-effective choice for standard machine-level applications where a separate PC is not required.