Tree Tech Digital Systems® modular architecture allows customers a cost effective approach to controlling their transformers. From a basic tap positioning control to a fully automatic voltage regulation scheme, customers can deploy the following IEDs individually or in combination,  to match each applications requirements:

Tree Tech Model AVR
The Voltage Regulator Relay - AVR is used to maintain the voltage in the secondary of power transformers equipped with on-load tap changers (OLTC). It indicates line voltages and loads, line current, active, apparent, and reactive powers, frequency, and power factor. The regulation is obtained when the voltage is deviated for a certain amount of time beyond the preset parameter, causing command pulses from the AVR to the OLTC, which raises or lowers taps, maintaining the secondary voltage. Details->

Tree Tech Model SPS
The Synchronous Paralleling Supervisor (SPS) consists of a microprocessor based electronic device capable of monitoring and modifying, through the on-lap tap changer (OLTC), the positions of power transformer taps. Both individually and simultaneous tap changes through interconnected SPS’s is possible via the RS-485 serial communication port. The SPS performs the paralleling of up to 6 three-phase transformers or 18 single phase transformers through the master-slave method.  Details->

Tree Tech Model PI
The model PI Position Indicator is a microprocessor based device capable of monitoring and changing the position of taps of power transformers through the on-load tap changer (OLTC). Using the Tree Tech PI, the traditional configuration of three separate devices position indicator, raise/lower key, and manual/auto selector is eliminated, as all these elements are integrated to the PI.  Details->

• Temperature Monitoring & Control

• Gas & Moisture Monitor

• Bag / Membrane Break Detector

• Circuit-Breaker Supervisor

• Auxiliary I/O and Data Acquisition

• Annunciation & Event Station

• Bushing Condition Monitor

• Communications & Networking

• Software Applications