By Donna Rider

Here is a look at some of the main aspects of creating a well-designed industrial HVAC control panel. A control panel is designed to do two things, provide electricity to the internal components and control an HVAC system. A completed control panel is logically arranged, easy to troubleshoot, visually pleasing and has adequate expansion room. All components and wire ends are labeled properly, sensibly, and in a method designed to last for the lifetime of the control panel.

Layout and Component Placement

A neat, well-organized control panel starts with a generously sized panel that allows for adequate spacing between voltage groups and individual components. Don’t forget to leave space for expansion both horizontally and vertically. Make sure you have plenty of room to work between components and plenty of room on the panel.  Inadequate space is one of the most common NEC violations.

Components should be laid out in a logical manner with attention to power needs and heat dissipation. For an energy efficient control panel try to use simple components such as relays, switches, etc., they produce less heat and are energy efficient. If simple components won’t do the job go to programmable logic controllers(PLCs) and any other components required to get the job done.

Best practices for HVAC control panel design is to group similar voltage rated components together. Starting with the components with the highest voltage levels at the top of the panel and working down from left to right with the lower voltage level components toward the bottom right. This design is logical and helps with troubleshooting. Heat producing components should be located at the top of the panel for proper heat dissipation. Be aware that PLCs and other components are sensitive to heat and should be placed on the control panel below all heat producing components leaving plenty of space between them.

For visual effect, place similarly sized components together within each separate voltage area with the larger components on the upper left and smaller to the lower right. Not only does an industrial control panel have to look nice it also must meet government regulations and standards.

Labeling

It is very important to properly label all components with syntax that makes sense. Every component needs to be properly labeled with the label clearly visible. The wire must be labeled on each end. The schematics should have the label designation for each of the components and wires on the control panel. The labels on the control panel must match the labels on the schematics.

Labels have to last the lifetime of the control panel for troubleshooting purposes, so they have to be durable. You cannot use handwritten labels, there are labeling regulations that must be met.

Wireway design

Various wiring methods are used in an industrial control panel. Make sure you use the right size wire for the job. For a professional looking control panel, carefully train the wire to stay in the ducts, don’t just hope the wire will stay where it belongs. Run wires as straight as possible within the ducts. It is easier to trace a wire if they don’t cross over each other too much. When training stranded wires, remember to bend carefully and slowly so you do not kink the wire and possibly break the small wires inside the sleeve.

Run wire in horizontal and vertical ducts, never run wire diagonally. Minimize the use of cable ties, they get cut and are never replaced. Try to leave a little slack in the wire but not enough that it is noticeable. All power wiring must meet clearance requirements.

Biography:

Donna Rider is a Technical Writer with more than 18 years experience researching, developing, managing, and producing on-line documentation and training videos. Ms. Donna Rider gained her expertise in technical writing during her highly successful career in several leadership roles. Specifically, Ms. Donna Rider wrote technical documents to assist the Help Desk Technicians troubleshoot calls from customers at Gateway and Wells Enterprises.

Sources:

  1. https://www.ecmweb.com/safety/ins-and-outs-electrical-labeling-part-1-2
  2. http://www.idc-online.com/technical_references/pdfs/mechanical_engineering/Control_Panel_Layout_And_Wiring_Best_Practices.pdf
  3. https://hennulat.wordpress.com/2013/05/13/control-panel-layout-and-wiring-best-practices/
  4. https://www.crossco.com/blog/what-comprises-good-control-panel-design
  5. https://www.mpofcinci.com/blog/industrial-control-panel-design-guide/
  6. https://hs-e.com/2018/03/best-practices-options-control-panels/
  7. http://www.ecmweb.com/ops-maintenance/make-sure-your-industrial-control-panels-are-ul-508-or-nec-compliant