ABB RET670 ——A Wise Investment in Protection

ABB RET670 ——A Wise Investment in Protection

The RET670/650 integrates over/under voltage and over/under frequency protection, making it ideal for power plant applications.The RET670/650 can share some of the functions of the generator protection or provide backup protection for the generator protection.The RET670/650 operates correctly over a wide range of frequencies to adapt to system oscillations or to changes in the system frequency during the starting and stopping of the generator.

Capacitor banks are among the more vulnerable to various anomalies in the power system, and the RET670 is configured with capacitor bank protection that detects dangerous operating conditions and trips capacitor units before they are damaged.
The RET670’s capacitor bank protection includes overcurrent protection, low-current protection, harmonic overload protection, reactive overload protection with reconnection suppression feature, etc. Together with the RET670’s original protection functions, such as unbalance protection based on overcurrent protection, it can provide complete protection for the capacitor bank.

In addition to the extensive overcurrent protection, the RET670 also includes negative sequence overcurrent protection, which detects all asymmetrical faults, grounded or ungrounded. This function is extremely sensitive and can detect very small current faults. The negative sequence overcurrent protection can also be used as a directional current protection, enhancing the integration with other objects.