Meeting the Growing Demands of the Electrical Industry

About Us​

United Electric Supply was founded by Norman Gronna in 1975 and was family-owned and operated for over 36 years, priding itself on customer service and support. In 2011 Main Electric Supply, Inc. acquired United Electric Supply, continuing its legacy and passion for the electrical industry. Now United Electric Supply consists of two branch offices and has expanded its growth and service throughout most of California. Main Electric Supply, Inc began its history in 1946 when Charles Vowels and Burt McCombs set out to meet the electrical industry’s growing demands and founded Main Electric Supply. Since the beginning, United Electric has maintained faithful relationships with electricians and builders who have grown accustomed to United’s service, supply, and reliability. We will continue to grow, embrace technology, and provide comprehensive solutions to industry challenges. Together we can build a bright and sustainable future.

Norm Gronna, Founder Of
United Electric Supply

Burt McCombs and Charles Vowels, Founders Of Main Electric Supply

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Product Bulletin for
Decora Smart® Wi-Fi® Lighting Controls

Create and manage home lighting activities that you can control from anywhere with Leviton Decora Smart Wi-Fi dimmers, switches, fan controls, outlets, smart plugs and more. Simply connect the devices to the free My Leviton app to control and automate lighting and scheduling from within your home or while away. Users can also pair the devices with other popular smart home solutions using the My Leviton app.

New Decora Smart 2nd Gen devices including a 600W Dimmer, 15A Switch, Mini Plug-In Dimmer, and Mini Plug-In Switch provide even more functionality, including integration with Apple HomeKitTM and compatibility with wireless Leviton Anywhere Dimmer and Switch Companions to control the devices from a secondary location within the home.


Remote Access from Anywhere. Use the free “My Leviton” app to add new devices to your home. Create schedules such as “Good Morning” to activate appropriate lighting at preset times. For instance, at 6:30AM every Monday through Friday, turn the bedroom lights to 25% and master bath lights to 50%. As well, Activities can be created for common lighting scenes so that, for example, you can manually set the lighting for “Movie Time” from the app as you begin your movie or create “Romantic Dinner” so lights can be dimmed from the app as you begin your meal.


Decora Smart Wi-Fi 2nd Gen devices can be added to an Apple HomeKit network and controlled with the native Apple Home app on your iOS device, providing compatibility with Siri for voice control.


Decora Smart Wi-Fi is compatible with products that support Amazon Alexa providing voice control of the load: “Alexa, dim living room lights to 25%”.


Ok Google, turn [My Leviton device name] On”. Works with the Google Assistant. Google Home is a voice enabled speaker powered by the Google Assistant. Easily control smart devices around the home.

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15497 Dupont Ave.
Chino, CA 91710
5474 Complex St. Unit 501
San Diego, CA 92123