Zimmer Electronic Systems
- Manufactures high precision power analyzer and meters.
- http://www.zes.com

High voltage Probes (Tektronics)
- For O'scopes, from Beta Lambda Instruments.
- http://www.blii.com/

Ameesco
- High voltage test equipment services and consulting. Specializing in the installation, commissioning and maintenance of all types of high voltage test equipment.
- http://ameesco.com/

Hipotronics
- Manufacturer of high voltage test and automatic test sets systems for users and manufacturers of power apparatus.
- http://www.hipotronics.com/

HV and EMC Test Equipment
- High voltage test equipment and EMC test equipment for the power utility, power apparatus, and electronic equipment industries.
- http://www.hvtechnologies.com/

Hachmann-IT
- Manufacturing of test-equipment for high voltage installations. From Germany.
- http://www.hachmann-it.de/

High Voltage Equipment Diagnostics Inc.
- Specializes in HV diagnostics and PM's for power utilities and sub-stations.
- http://www.hved.com/

Alff Engineering
- PDC-ANALYSER equipment for on-site evaluation of the properties of mixed insulation as found in high voltage transformers.
- http://www.alff-engineering.ch/