ETT-02 - Voltage regulator for transformers
The microprocessor-based ETT-02 transformer tap changer voltage regulator is designed for automatic regulation of the low-voltage side voltage or the transformer tap position (ratio). It can operate with all transformers equipped with on-load tap changers.
Equipping the regulator with a dual set of current and voltage measuring transformers allows it to stabilise a selected parameter (voltage or tap position) of:
- two-winding transformers,
- two-input two-output transformers,
- three-winding transformers.
To prevent switching when limit values are reached, the regulator is equipped with the following interlocks:
- overvoltage,
- undervoltage,
- overcurrent,
- tap position limit (blocking operation when the extreme tap position is reached).
Design
The ETT-02 regulator is housed in a split, three-part Bopla Combi Card II enclosure, providing easy access to all components. It is also available as a standard 19-inch EURO cassette for backplane or cabinet installation.
The use of detachable external connectors arranged in functional groups facilitates commissioning and servicing.
The controller is designed as a three-board system with functionally separated blocks:
- power block, current and voltage measurement circuits, and output relays,
- electronic control system block,
- parameter setting and display block.