1.8 Toll Restriction (TRS)/Call Barring (Barring) Features
1.8.3Extension Lock
Description
An extension user can change the TRS/Barring level of the telephone ( 
1.8.1 Toll Restriction (TRS)/Call Barring (Barring)) so that other users cannot make inappropriate trunk calls. An extension personal identification number (PIN) is used to unlock the telephone ( 
1.26.1 Extension Personal Identification Number (PIN)).
This feature is also known as Electronic Station Lockout.
Conditions
•This feature also restricts changing the FWD destination. ( 
1.3.1.2 Call Forwarding (FWD))
•Remote Extension Lock
Overrides Extension Lock. If an extension assigned as the manager sets Remote Extension Lock on an extension that has already been locked by the extension user, the user cannot unlock it. If a manager extension unlocks an extension that has been locked by the extension user, the extension will be unlocked.
This feature is also known as Remote Station Lock Control.
•TRS/Barring Level
COS programming determines the TRS/Barring level for Extension Lock ( 
TRS/Barring Level for Extension Lock [510]).
User Manual References
User Manual
1.5.3Preventing Other People from Using Your Telephone (Extension Lock)
2.1.1Extension Control
