BAU+ Sensor | BAU Sensor | Bushing Sensor

BAU+ Sensor (Bushing Adapter Unit)

BAU+ Sensor

The Bushing Adapter Unit (BAU+) sensor serves multiple purposes which eliminates the need to purchase a unique sensor for each application. It provides

  • Bushing signals for bushing insulation characteristics
  • Partial discharge in bushings and transformers
  • Additional circuitry for noise filtering using Rogowski coils

The BAU+ sensor has a robust, environmentally hardened design rated to IP-67 specifications. These sensors are ideally suited for use in power transformers, isophase bus ducts, and HVCTs.

BAU+ Sensor taken apart

Easy Removal and Installation for Offline Testing

BAU+ Sensors are installed in the test tap of the bushing. If a test tap isn’t available, the voltage tap may be used. BAU+ Sensors are designed with three sections: body, adaptor and cable connector. The body of the sensor can be easily detached from the adapter by the removal of three screws. Once the body is disconnected, the test tap of the bushing can be accessed directly or the adapter can be removed from the bushing to provide additional room when needed. The adapter head and contact change to accommodate the design of the bushing tap, the body and cable connector stay the same.

Three Levels of Protection

  1. Open Circuit / Voltage Limiter – Six voltage limiters provide open circuit protection. A current balance circuit is used to distribute the stress equally between limiters. Dynamic Ratings offers the lowest open circuit protection in the industry.
  2. Surge Protection – Surge protection provides safety for equipment and personnel. Two surge protection circuits provide protection for switching and system transients.
  3. Fail Safe Circuit – A fail safe circuit automatically grounds the tap inside the body of the sensor should the open circuit and / or surge protection fail.
BAU+ Sensor in the field

More About the BAU+ Sensor

  • Each sensor provides signals for imbalance, bushing leakage current, capacitance, power-factor and partial discharge measurements.
  • Three levels of protection: open circuit / voltage limiter, surge protection, and fail safe circuitry.
  • Easy removal for offline testing.
  • 50+ custom adapters to suit various test tap styles.
  • Provides Rogowski coil amplifier and cable for aid in partial discharge noise filtering.
  • 50 Ohm coax cables provide longer distances of accurate signal transmission.

Support Requests

If immediate response is required, please directly contact your local Dynamic Ratings location:

Asia Pacific
+61 3 8544-0700
[email protected]

+1 262 746 1230 x3
[email protected]

+44 1617 681111
[email protected]


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HVCT Sensor

High Voltage Current Transformer Sensor

The BAU-HVCT is a Bushing Adapter Unit (BAU) sensor designed for use on High Voltage Current Transformers (HVCT). It is a compact sensor commonly installed in series with the grounding wire in the CT junction box. The BAU-HVCT Sensor serves multiple purposes which eliminates the needs to purchase a unique sensor for each application. It monitors and measures the power factor, capacitance values, and the leakage current to calculate the imbalance of the system. With connection to the C50 Bushing Monitor, data trending can track faults and indicate a potential problem. Download the brochure.