Electrical Control Panel: What It is and Why You Need One

January 26, 2021

Industrial equipment and machines require defined functions and orderly control to achieve their various process goals. Electrical control panels carry out these functions within manufacturing equipment. An understanding of what they are highlights their critical importance to industry.


In its simplest terms, an electrical control panel is a combination of electrical devices which use electrical power to control the various mechanical functions of industrial equipment or machinery. An electrical control panel includes two main categories: panel structure and electrical components. 


The structure of an electrical control panel is a combination of an enclosure and a back panel, similar to a breaker box in a home or office.


The enclosure is a metal box which varies in size and is typically made of aluminum or stainless steel. The number of doors (usually one or two) needed on the enclosure determines its size in most industrial applications. The enclosure will come with a UL safety rating (508A is typical) an IP rating, and/or a NEMA classification. These listings help users determine properties such as:

  •    –   Indoor/outdoor use

  •    –   Waterproof/water resistance

  •    –   Dust/solid contaminants proofing

  •    –   Hazardous conditions rating

  •    –   Explosion-proof rating

These various classifications should be printed on a metal plate and attached to the enclosure for easy identification and reference. 

Back Panels

A back panel is a metal sheet mounted inside the enclosure that provides structural support for DIN rail mounting and wiring ducts. DIN   metal rails feature standardized dimensions and provide a mounting structure for electrical devices. Wiring ducts provide for the routing and organization of wires while also assisting in the control of electrical noise between devices inside the box.


Eight types of electrical components exist within an electrical panel enclosure which define and organize the several different functions carried out by the panel. These components include: 

  •    –   Main circuit breaker. This is like the disconnect of the main electrical panel leading into a home or office. Main circuit breakers handle between 120V–480V in most industrial applications.

  •    –   Surge arresters. This component prevents lightning strikes or utility power surges from damaging the electrical components inside the panel due to overvoltage.

  •    –   Transformers. Depending on the incoming voltage, transformers may reduce voltage to 120V for various components or step down voltage to 24V in instances where incoming power is 120V.

  •    –   Terminal blocks. These blocks help to organize and distribute the array of wires coming from various sources to different electrical devices.

  •    –   Programmable Logic Controller (PLC). This is essentially a CPU contained inside the control panel. This unit is the brains of the control panel, providing monitoring and control of the various mechanical processes. In will include various inputs and outputs to and from mechanized functions of the production equipment.

  •    –   Relays and contactors. These on/off switches control mechanized functions based on commands from the PLC. Smaller relays control functions like lights and fans. Larger relays, called contacts, control more advanced functions like motors.

  •    –   Network switches. The communication hub of the control panel, network switches facilitate communication between the PLC and the various network compatible devices on the production line.

  •    –   Human Machine Interface (HMI). These components allow an operator to monitor or control certain functions of the machinery. Common HMIs include video monitors, joysticks, buttons, switches, and keyboards.


The design of a custom electrical control panel will depend upon the complexity of the system it operates. Designs can include a simple electrical relay system or a more complex PLC system with single or multiple PLC networks with IIoT or SCADA integrations. Indicators that your organization might need a custom panel design include a need for more advanced operation of various production operations; more cohesive, universal control of systems; and/or a need for improved HMI.


Maintenance is another key consideration for electrical control panels. Facilitating maintenance is a critical element in custom electrical control panel design. Maintenance elements should include: 

  •    –   Clearly labeled components, wiring, and terminals

  •    –   Capability to monitor the status of the various electrical connections

  •    –   Control of particulates and dust within the enclosure

  •    –   Pest control measures


Electrical control panels are essential for industrial automation. They provide higher-level monitoring and control of the various functions of production machinery, allowing manufacturers to define, organize, and meet production objectives. 

IndustLabs has more than 15 years of experience in the design and construction of electrical control panels serving industries such as: 

  •    –   Food & beverage

  •    –   Oil & gas

  •    –   Pharmaceutical

  •    –   Power generation & power circuit

  •    –   Manufacturing

  •    –   Fluid handling

  •    –   Material handling




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