Which companies manufacture transformer oil testing equipment?

Oil test equipment is made by several well known electrical test and diagnostic instrument manufacturers, including companies producing BDV testers, moisture meters, and dissolved gas analyzers. Selection should be based on the test standard support (IEC or ASTM), accuracy, repeatability, calibration traceability, and field ruggedness. For DGA, consider lab services versus portable analyzers, and validate results against a certified lab periodically to keep confidence in decisions.