GE Industrial Solutions Entellisys System User Manual - Manual (Page 11)

Description of operation 11
1
1 System architecture
The Entellisys™ Low-Voltage Switchgear architecture is unique. The central processor unit (CPU)
is the basis of this new protection-and-control architecture. The CPU provides protection and
control functions over the entire low-voltage switchgear system.
The key advantage of this architecture is that the CPU has all the information from all circuit
breakers simultaneously. The architecture also has built in redundancy to increase system
availability.
Figure 1-1 Entellisys LV Switchgear simplified architecture
1.1 Description of operation
Current transformers (CTs) and potential transformers (PTs) measure current and voltage and
transmit the analog information to the EntelliGuard™. The Messenger digitizes and sends the
information over the Messenger communication network to two redundant CPUs.
The CPUs make protection decisions, capture events, process waveform data, and provide
status information. For example, if the CPUs identify a trip condition at a circuit breaker, the CPU
alerts the EntelliGuard Messenger at that circuit breaker, which then actuates the circuit breaker
and returns the circuit breaker status to the CPU.
Modbus
®
communication, an open industry standard protocol, is provided as an interface to
external components such as the Entellisys HMI, SCADA, or other Building Automation Systems.
The Human Machine Interface (HMI) is the central user interface for the system. HMIs are
touchscreen computers located in-gear or near-gear (see
Touchscreen HMI on page 22 ) and
Remote HMIs are available for desktop users who want to view the switchgear from their office.