Redundant station bus communication according to IEC 62439-3 Edition 1 and IEC 62439-3 Edition 2 are available as options in 670 series IEDs. IEC 62439-3 parallel redundant protocol is an optional quantity and the selection is made at ordering. Redundant station bus communication according to IEC 62439-3 uses both port AB and port CD on the OEM module.

For systems which are running asynchronous a synchronizing function is provided. The main purpose of the synchronizing function is to provide controlled closing of circuit breakers when two asynchronous systems are going to be connected. It is used for slip frequencies that are larger than those for synchrocheck and lower than a set maximum level for the synchronizing function.

Four step negative sequence overcurrent protection (NS4PTOC) has an inverse or definite time delay independent for each step separately.All IEC and ANSI time delayed characteristics are available together with an optional user defined characteristic.

The Model H90 servers are connected to the Foxboro Evo Control Network (the control network) on a Foxboro Evo system through dual Ethernet PCIe cards. It can also be simultaneously connected to a generic Ethernet based information network via the two integrated Ethernet ports. Standard security practices should be followed when this is done.

Employing an industrial-grade electromagnetic interference-resistant design, control cables and excitation cables must be wired separately (spacing ≥30cm); grounding requires ≥4mm² copper wire, achieving low-impedance connection (≤1MΩ) through toothed washers to avoid static electricity accumulation (do not wear synthetic material clothing, touch grounded metal to release static electricity before operation); supports ABB 800xA, AC800M DCS systems and third-party SCADA platforms (compliant with IEC 61850, Modbus RTU, CAN, and other protocols); modular stacking expands the number of I/O points, compatible with modules such as PCD231A101 in the same series, and can be mixed for system expansion.

Built-in power system stabilizers (PSS), such as PSS2A/2B, accelerate power integration by synthesizing dual input signals of speed and electrical power to suppress low-frequency oscillations; PSS4B's multi-band compensation technology addresses wide-band damping requirements. Jingdezhen Power Plant has achieved stable operation of its 660MW units across multiple scenarios through PID regulation and adaptive PSS, and supports remote diagnostic tools (such as AVRview) for condition monitoring and parameter adjustment.