Evaluation of new materials for D.C. motors and generators

The large number of insulation materials now available and the increasing rate at which new materials are being introduced make it more and more difficult for an insulation engineer to stay abreast of his field. The overly enthusiastic and optimistic claims made by some manufacturers and vendors, many of whom are applying classifications and designations to materials and systems where tests to establish such designations have not yet even been formulated, make it essential that screening and evaluation tests be an integral part of any acceptance or use proposal.