This specification applies to transformers for power and lighting having windings insulated with Class A and Class B materials, as defined in Appendix I, including auto-transformers, polyphase transformers and singl-phase transformers, wheter the latter are used singly or connected in any polyphase arrangement. Reactors shall comply with this specification in so far as the high-voltage tests are concerned, and if continuously rated the temperature-limits given in the specification also apply. It does not apply to instrument transformers, traction transformers mounted on electric locomotives or other vehicles and used for supplying electrical energy for traction, testing transformers, auto-transformer starters or induction regulators.