April 2013

Power factor correction

Two new controllers with expanded functionality

TDK Corporation presents two new types of the BR7000 series of EPCOS power factor controllers. The BR7000-T power factor controller offers 15 transistor outputs instead of 15 relay outputs. It is designed for applications that require fast switching operations and enables delay-free switching of thyristor modules, such as the EPCOS TSM series. The second innovation is the EPCOS BR7000-I with an RS485 interface, which can be used for embedding into networks, for controller coupling and for visualization via PC.

The BR7000-T offers various control modes, for example, switching of 15 steps with three-phase capacitors, switching of 15 single-phase steps in L-N or L-L operation, or mixed operation. The switch on and off times of capacitor steps can be selected between 50 and 1000 milliseconds. The BR7000-T has an illuminated graphic display; the BR7000-T/HD has an OLED display to ensure better visibility in poor lighted surroundings.

The BR7000-I/S485 is delivered with Windows-based BR7000-SOFT software and allows the evaluation and further processing of measured grid data via PC. The additional external input of the BR7000-I/S485 can be individually programmed, for example, for a second set of parameters. Also, the controller features a freely programmable message-relay, for instance, to trigger a fan or for status messages. An internal clock marks all recorded values and messages with a time stamp, allowing a better evaluation of all values.

The operating voltage covers 110 V AC to 230 V AC with a very low consumption of < 3 VA when all outputs are activated.


  • Power factor: The ratio of active power to the apparent power, which consists of active power and reactive power and is drawn by an electrical installation during operation. Ideally, the power factor is as close to 1 as possible.
  • Power factor controller: Measures the reactive power and switches the steps of a capacitor bank to the power network via thyristor modules until the power factor is corrected.

Main applications

  • Power factor correction in single- and three-phase industrial power networks

Main features and benefits

  • Fast switching of PFC capacitors
  • Embedding into PC networks and visualization, storage and processing of power network parameters



Read more