REX521BBHGLB01C Power module
The REX521BBHGLB01C is a power module that is part of ABB’s REX521 series of feeder protection relays. Provides efficient medium voltage network protection, measurement, monitoring and basic control functions. Its application field mainly includes power system, especially feed line protection.
It has a variety of protection functions, such as three-phase overcurrent protection, non-directional and directional ground fault protection, thermal overload protection and phase discontinuity protection. In addition, the relay can also monitor the power quality in the network, such as measuring harmonics.
The REX521BBHGLB01C power module also contains static testing technology, which is a technique used to detect software components and code errors during the software development lifecycle, helping to find and fix errors before the application is executed.
The application areas of REX521BBHGLB01C are mainly focused on feed line protection in power systems.
This product is part of ABB’s REX 521 series of feeder protection relays and provides efficient medium voltage network protection, measurement, monitoring and basic control functions. It has a variety of protection functions, such as three-phase overcurrent protection, non-directional and directional ground fault protection, thermal overload protection and phase discontinuity protection, to ensure the stable operation of the power system.
In addition, REX521BBHGLB01C features static testing technology, a technique used to detect software components and code errors during the software development lifecycle, helping to find and fix errors before the application is executed.
Overall, the REX521BBHGLB01C is a powerful and widely used power system protection device. 
