ZTZ Services International specializes in developing and manufacturing transformer bushing monitoring systems for GSU Transformers, Substation Transformers, and Substation Circuit Breaker bushings. They are the sole value-added reseller of the Hydrocal range of on-line dissolved gas analysis (DGA) systems for large power transformers. Additionally, ZTZ offers lower-cost monitoring solutions for underground network transformers. Their expertise lies in detecting insipient problems in high-voltage bushings, partial discharge detection and analysis, high-voltage underground cable monitoring, pothead monitoring, and fault gas monitoring systems. ZTZ also provides expert field service for commissioning and servicing of their monitoring systems, emphasizing the importance of preventing failures and improving maintenance targeting for their customers.