The Pioneer in Transformer Monitoring

ZTZ on-line transformer monitoring systems help utility asset managers by detecting electrical nuances which are known to be indicators of near-term failure.  Over 5000 ZTZ systems are in service world-wide.  Since ZTZ was founded in 1997, hundreds of transformer bushings with symptoms of failure have been detected and taken out of service before catastrophic failure occurred.  All ZTZ systems are hand-built in USA and carry a lifetime warranty.  ZTZ Services is a Veteran Owned Business.

ZTZ Services is Trusted by the World's Largest Power Companies

ZTZ Services has pioneered the development of on-line transformer bushing monitoring since the 1970s.  Our transformer monitoring systems have been further developed and refined ever since.  ZTZ monitoring systems use exclusive algorithms and methods to determine bushing health with the highest confidence level using only one connection to the bushing C1 test tap.  All ZTZ monitoring systems carry a lifetime warranty.  We offer full turnkey installation services.

Accurate and Reliable

ZTZ Services takes pride in the extremely high quality of their products. Bushing sensors are hand-made from billet aluminum or stainless steel in the USA. Redundant voltage-limiting circuitry ensures safety to installers in the event open ground connection. ZTZ bushing monitors provide condition data of the bushings while they are operating at system voltage. The measured parameters correspond closely to those from traditional off-line tests.

Innovative Solutions

ZTZ Services has continued to innovate where competitors have become stagnant. In 2012, ZTZ originated a new bushing monitor test method which uses both high and low side bushings. This method helps to eliminate uncertainty from varying system voltages or ambient temperatures outside of the optimal range. In 2018, ZTZ was awarded US Patent 10,126,348 B2 for our new method of detecting GIC with our existing bushing sensors, saving the cost of many extra sensors that are required by competing systems.

American-Made and serviced

ZTZ Services is a Veteran-owned company. All products are hand-made in USA. ZTZ service and support is based in Miami, Florida. All ZTZ monitoring products are available with full turnkey installation, field installation engineers dispatched from the home office in Miami, Florida.

Have Questions? Contact an application engineer to get more information

TransMAX 1000

ZTZ TRANSMAX 1000 is a compact monitor which combines Bushing Monitoring with Partial Discharge (PD) detection using one common sensor attached to the bushing C1 test tap. The TRANSMAX1000 also is used for monitoring the condition of CCVTs.

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MTE Hydrocal DGA Monitor

The Hydrocal on-line Dissolved Gas Analyzer for oil-filled power transformers is produced by MTE in Germany. There are eight models of Hydrocal in the product range, each with a different number of individual measurements for key fault gasses. The basic model (1001+) measures moisture, Hydrogen, and Carbon Monoxide and four other hydrocarbons as a composite measurement. The top of the range (1009) gives nine individual key gas measurements of concentration. There is also a portable field test set for ten key fault gasses in the range.The Hydrocal is well known for reliability, accuracy, and small size. No consumable gasses or products are used for operation of the Hydrocal. The combination of ZTZ transformer bushing monitor and Hydrocal makes a fully-featured transformer monitoring system and all aspects of the system are brought to common management dashboard software produced by ZTZ. ZTZ Services is the official distributor and service center for Hydrocal in North America.

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ZVCM Bushing Monitor

The ZVCM is presently in service on over 10,000 bushings, world-wide. The ZVCM can be used on any bushing with a test tap, system voltages to 765 kV. It is also used on oil circuit breakers as a life-extension strategy.

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CCVT Max is a proven health monitoring system for CCVTs. With CCVT Max, the symptoms of many problems can be detected. CCVT max goes far beyond typical voltage monitoring. Simple voltage monitoring cannot preserve system security while coping with normal system voltage swings and imbalance, and other outside influences on voltage that can be mistaken for CCVT problems. CCVT Max is the ideal retrofit monitor to use for your life extension strategy, ensuring crew safety in energized substations where CCVTs are installed.

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Asset Management and Engineering Services

We provide expert analysis, design and creative solutions to meet your unique needs.

Training and Education

Industry-leading support, on-site education and a unique two-day user meeting in Miami, FL to learn our systems and software.