ELRO DWH SERIES VIDEO SECURITY SYSTEM - Manual (Page 33)

System Upgrade
To upgrade the firmware from the vendor website, you must download
and store it in the SD card root directory.
Refer to Upgrading Your System Software (p.33 and p.36)
Language
English is the default language. If you change the language, all system
settings default to the original factory settings. You will have to reenter
any specialized settings.
This screen should display: From the pop up menus,
tap the following icons
1. Select the language required. The Restore Default Settings screen
displays.
2. Tap OK to continue. The system will shutdown in about 5 seconds.
3. When the system restarts, it will ask you to perform the touch screen
calibration. Follow the instructions on the screen.
4. Select the frequency setting by tapping the frequency icon (50Hz /
60Hz). Make sure the frequency setting complies with local electrical
regulations.
Note:
In general the frequency for Europe is 220-240 volt, at 50 hertz frequency
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