Made in California

Vanguard Instruments Company, Inc.

Vanguard Instruments Company was founded in 1991. Currently, our 28,000 square-foot facility houses Administration, Design & Engineering, and Manufacturing operations. From its inception, Vanguard’s vision was, and is, to develop and manufacture innovative test equipment for use in testing substation EHV circuit breakers and other electrical apparatus.

Products and Services

We are a leading manufacturer of substation testing equipment including: Circuit Breaker Analyzers, Transformer Turns Ratio Testers, Current Transformer Testers, and Circuit Breaker Contact Resistance Meters. We are ISO 9001:2008 certified (Cert. no. US07/934) and we are a certified Minority Business Enterprise (MBE).

Manufacturing Processes

Circuit Board Design - assembly of components to final product.

Contact This Manufacturer

Company Name: Vanguard Instruments Company, Inc.

Category: Electrical Equipment

Location: Ontario, CA

Contact Person: Mike Hai Nguyen

Phone: (909) 923-9390

Fax: (909) 923-9391

Email: @


Featured Products


Vanguard CT-7000 S3 Circuit Breaker Analyzer


Vanguard EZCT-2000C Current Transformer Tester


Vanguard 28,000 Square Foot Facility