Web HMI - Arc protection - Bay control and measurement - Merging unit - Transformer protection - 2 winding - Feeder protection - Voltage regulation - Capacitor bank protection - Grid automation - Busbar differential protection (high impedance) - Line differential protection - Back-up protection - Motor protection - Busbar protection (voltage and frequency) - Interconnection protection - Generator protection - Power management/Load shedding - Operation Manual - REX615 Protection and control - PCL2 - IEC - ANSI - 01.04.2026

REX615 Operation Manual

The WHMI allows secure access to the protection relay via a Web browser. The Web server is forced to take a secured (HTTPS) connection to WHMI using TLS encryption. The WHMI is verified with Google Chrome, Mozilla Firefox and Microsoft Edge.

Note:

WHMI is disabled by default. To enable the WHMI, select Main Menu > Configuration > HMI > Web HMI mode via the LHMI. Reboot the protection relay for the change to take effect.

WHMI offers several functions.

Table 1. Web HMI main groups and submenus
Main groups Submenus Description
Dashboard Used to see an overview of the protection relay including status, measurements, single-line diagram and latest events
Device

Monitoring

Information

Self-supervision

Single Line Diagram

Goose and SMV

Clear

Change Password

About

Used to navigate to monitoring, information, self-supervision, single-line diagram, Goose and SMV or clear pages
Measurements

Measurements

Phasor Diagrams

Used to navigate to the measurements or phasor diagrams
Recordings

Events

Disturbance records

Fault records

Load Profile Record

Used to view the events, disturbance records, fault records and load profile records
Import/Export

Report Summary

Import/Export Settings

Parameter List

Used to export a parameter list or a report summary, and to import and export settings
Parameters Used to view the menu tree structure for the protection relay's setting parameters
Language selection Used to change the language
Logout Used to end the session

The menu tree structure on the WHMI is almost identical to the one on the LHMI.

Figure 1. Example view of the Web HMI

The WHMI can be accessed locally and remotely.

  • Locally by connecting the laptop to the protection relay via the front communication port.
  • Remotely over LAN/WAN.