To talk to each party alternately
Talk to the 
other party.
During a conversation
PT/PS
Press TRANSFER.
TRANSFER
To continue
 Executive Busy Override Deny
A preprogrammed extension user can prevent his calls from being interrupted by another extension user
(Default: Allow other users to interrupt calls).
To set
Off-hook.
On-hook.
Enter 1 to prevent
or 0 to allow.
PT/SLT/PS
Prevent
Allow
1
0
OR
Enter    733.
3 37
C.Tone
1.3.25  Extension Dial Lock
You can lock your extension so that other users cannot make unauthorized outside calls.
This feature is also known as Electronic Station Lockout.
To lock
Off-hook.
On-hook.
PT/SLT/PS/SIP Extn.
Enter    77. 
Enter 1. 
177
C.Tone
78 Operating Manual Document Version  2013-05  
1.3.25 Extension Dial Lock