Citizen CT-S851 Manual De Usuario página 52

4.5 Key Lock Function
Press and hold the MENU button while the printer is running to be able to
change the memory switch settings.
Activate the key lock to prevent making changes by mistake.
LOCK icon
FEED
Button 3
Setting the key lock
To set the key lock, press and hold button 3 (for at least three seconds).
MENU disappears, and the LOCK icon appears.
In this condition, it is not possible to enter the memory switch setting mode
even if you press and hold the MENU button.
Releasing the key lock
To release the key lock, press and hold button 3 (for at least three seconds).
The LOCK icon disappears, and MENU appears.
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