High Voltage

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/

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/

Basics of High Voltage Probe Design
Covers theory, tips, practical advice, sources, parts, links to other sites, and information about HV probes uses and design.
http://www.repairfaq.org/sam/hvprobe.htm

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/

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

Rectifiers and Electronics
Manufacturers of AC/DC high voltage and high current testing equipment, spark testers, industrial voltage stabilizers, AC and DC welding equipment, battery chargers. New Delhi, India.
http://www.testingequipments.in

Sphere Gap Breakdown Voltage Tables
How to measure high voltages with some precision.
http://home.earthlink.net/~jimlux/hv/spherev.htm

Vitrek
Manufactures high potential testers for both AC and DC measurements including a complete ground safety, fault locating, and measurement systems.
http://www.trirep.com/vitrek.htm

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