ZVCM-1001 Bushing Monitor
The ZVCM stands alone in build quality and value. The ZVCM simultaneously monitors the leakage current present at the test taps of the bushings. Depending on the configuration, up to five separate algorithms are used to determine bushing health. While competing systems use only two or three test methods, the ZVCM includes five, so the confidence level in ZVCM bushing alarms is extremely high.
There has never been a reported false positive from a ZVCM bushing monitor.
The ZVCM is a two-part system that includes the Bushing Sensors and the ZVCM monitoring system cabinet
The bushing sensor is the heart of the monitoring system. The bushing sensor replaces the grounding cap which is in-place when the bushing is in service. ZTZ bushing sensors are made from the highest quality billet aluminum or 304 stainless steel. Redundant voltage-limiting circuitry is installed inside the sensor to protect field technicians in the rare case that the ground becomes disconnected; personnel safety is the top priority.
ZTZ bushing sensors are made to exacting mechanical standards so there will be no risk of damage to the bushing test tap or surrounding threads. Aspects such as gasketing, depth, thread size, taper, contact material, and approach angles are all considered for every installation.
The highest quality co-axial RG-48 signal cable is mated to the bushing sensor in a controlled environment by skilled ZTZ technicians. Water-tight flexible conduit may be used for the field installation, or not, depending on the preference of the transformer operator. ZTZ bushing sensors are completely made in USA, not China, not Mexico.
ZVCM Bushing Monitor System Cabinet
The compact design of the ZVCM makes it easy to mount in the transformer control cabinet, included on a new transformer by the OEM. As a retrofit system, the ZVCM is usually installed inside a NEMA rated 304 Stainless Steel enclosure. The enclosure may be installed on existing framework, Unistrut, or on stainless steel pedestals on the concrete pad.
The ZVCM is also useful for life-extension and supervision of oil circuit breakers.
If GIC (Geomagnetic Induced Current) is a concern at your utility, the GIC monitoring feature can be easily added to the ZVCM, using the same bushing sensors. This is a patented technique, not available from any other supplier.
The IP54 enclosure includes vent and drain, power supply, circuit breaker, grounding switches, and heater.
Network converters, media converters, and other accessories may be included according to project requirements.
For projects requiring more than six sensor inputs from bushings, or from CCVTs, two ZVCM monitor systems may be installed in a single, larger, enclosure.
Frequently Asked Questions
The ZVCM hardware reports bushing and its own operational condition. The ZVCM proprietary software is also designed to detect abnormal operation and alert users remotely.
The ZTZ bushing monitoring products have an over 95% detection rate.
Over 3500 units are installed.