Nautilus Hyosung MS500 Operator's Manual page 22

Chapter3. For the beginning operator
3-6 © 2017 Nautilus Hyosung Inc. All Rights Reserved.
This is an option that is only available while the lock is in Shelved Mode and is
intended only for temporary use after the ATM is deployed but before the lock is
activated. It is not recommended to keep the Cencon lock in this Shelved Mode
condition, due to lack of security and control.
Required Items:
Change Key, Current Shelved Mode Combination
<Note!>
You can only change the Shelved Mode combination while operating in Shelved Mode.
Once a lock is "activated" in any mode, the Shelved Mode combination returns to the
Factory Default of 50-25-50
To change the Shelved Mode Combination:
1. Power Lock  EC
Turn the Dial to the left (CCW) until "EC" (Enter Combination) is displayed.
2. EC  Enter Shelved Mode Combination  OPr
Enter the current Shelved Mode combination (either 50-25-50 or a changed Shelved
Mode combination) by sequentially pressing those digits on the lock keypad. The
numbers will be displayed on the LCD as they are entered. When the combination
has been correctly entered, the LCD will read OPr, meaning "OPen right."
3. OPr  Retract Bolt
Turn the Dial to the right (CW) to retract the bolt
4. Open Door
5. Insert Change Key
Insert the change key into the change key socket on the back of the lock.
WARNING:
Do not close the door.
Leave the door open during this process until your are comfortable opening the lock
with the new combination.
6. Extend Bolt
Turn the Dial to the left (CCW) to extend the bolt.
7. Power Lock 
Turn the dial to the left (CCW) until
Enter Combination) is displayed.
 Press #8  EcF
8.
Press the "#" button followed by the "8" button. EcF (Enter current Factory
combination) will be displayed
(the Change Key symbol along with
Operator Manual