Elo TouchSystems ET2239L User Manual page 16

You are able to lock and unlock the OSD feature. When the OSD is
locked, no OSD can be displayed or used. The monitor is shipped in
the unlocked position.
To lock the OSD:
1 Press the MENU button and UP button simultaneously for 2
seconds. A window will appear displaying "OSD Unlock."
2 Continue to hold the buttons down for another 2 seconds and the
window toggles to "OSD Lock."
Power Lock/Unlock
You are able to lock/unlock the Power feature. When the power is
locked, pressing the power switch will not turn off the monitor. The
monitor is shipped in the unlocked position. To lock the power:
1 Press the MENU button and the DOWN button simultaneously for
2 seconds. A window will appear displaying "Power Unlock."
2 Continue to hold the buttons down for another 2 seconds and the
window toggles to "Power Lock."
NOTE: By default, the OSD screen will disappear if
no input activities are detected for 30 seconds.
Elo TouchSystems ET2239L User Guide 16