North American Substation Services (NASS) is a nationally-recognized expert specializing in transformer and substation appara ... tus installation, services, and repair. Our management and highly skilled field-based force have received specialized training and are among the most experienced in the industry. NASS is dedicated to providing quality service and solutions that optimize the reliability of transformers and other substation equipment. Our customers know us as a trusted resource in the substation field with established long-term relationships grounded in integrity, professionalism, and value. read more