ABB的REF545馈线终端保护装置是一款功能强大的设备，具备以下特点：

1. 广泛的适用性：REF545馈线终端可用于不同类型的开关设备，如单母线、双母线和双工系统，还可用于保护、控制、测量和监视中压电网。
2. 强大的保护功能：该装置支持不同类型的网络，如隔离中性网络、谐振接地网络和部分接地网络，并具备过温、过流等保护功能。
3. 自动化功能：REF545馈线终端配备了大量的PLC功能，可以将变电站自动化所需的多种自动化和顺序逻辑功能集成到一个单元中。

在应用场景方面，REF545馈线终端主要应用于中压电网的保护、控制、测量和监视。其应用范围覆盖了中型三相异步电机以及用于无功功率补偿的并联电容器组的保护和控制。

至于其保护作用，除了基本的保护、测量、控制和状态监测外，REF545馈线终端还可以用于电能质量的监测，同时具备检同期、频率保护、电容器保护等功能。此外，它还支持RTD/模拟量测量模块，可用于温度、电流/电压的测量和mA量的信号输出。

总的来说，ABB的REF545馈线终端保护装置具备高度的灵活性、适应性和功能性，是中压电网中不可或缺的重要设备。

ABB's REF545 feeder terminal protection device is a powerful device with the following characteristics:

Widely applicable: REF545 feeder terminals can be used for different types of switchgear, such as single bus, double bus, and duplex systems, and can also be used for protection, control, measurement, and monitoring of medium voltage power grids.

Powerful protection function: This device supports different types of networks, such as isolated neutral networks, resonant grounding networks, and partially grounded networks, and has protection functions such as over temperature and over current.

Automation function: The REF545 feeder terminal is equipped with a large number of PLC functions, which can integrate various automation and sequential logic functions required for substation automation into one unit.

In terms of application scenarios, REF545 feeder terminals are mainly used for protection, control, measurement, and monitoring of medium voltage power grids. Its application scope covers the protection and control of medium-sized three-phase asynchronous motors and parallel capacitor banks used for reactive power compensation.

As for its protective function, in addition to basic protection, measurement, control, and status monitoring, the REF545 feeder terminal can also be used for monitoring power quality, and has functions such as synchronous detection, frequency protection, and capacitor protection. In addition, it also supports RTD/analog measurement modules, which can be used for temperature, current/voltage measurement, and mA signal output.

Overall, ABB's REF545 feeder terminal protection device has high flexibility, adaptability, and functionality, and is an indispensable and important equipment in the medium voltage power grid.