button in the CPU board. It is deliberately kept separate from all programming functions. Another use for it, however, is as a “masterkey” code. For example, consider a facility with multiple DK-26’s under the control of different departments. Each department might want to employ different Program and User codes to restrict cross access but a common Hard code could be established for all of the units so that security management personnel could enjoy universal access. This Hard code will never be lost from keypad operations (the CPU board has to be accessed).
4.4 SUBSET CODES
When you recognize that the DK-26 accepts multiple codes of different lengths, it is possible that one code will be a subset of another. For example, suppose you programmed “1-3-3-5-8” and then programmed “3-3-5” as another code. When you try to enter 1-3-3-5-8, you can’t complete the entry because when the unit sees the sequence 3-3-5, it will operate. A real problem could occur if a User code was a subset of the Program code. The unit could not be put into program mode from the keypad.
The DK-26, however, avoids this problem by rejecting any code that is a subset of another code in memory. It signals this rejection by showing the single red (error) flash instead of the two-flash confirmation signal. You’ll get the same error if you try to enter a duplicate code. If you are trying to enter a code and see it rejected by the error signal, carefully check your list of other codes. You are probably attempting to enter a subset code. If the security procedures of the installation allow individuals to choose their own codes without reference to a list, the users need to be advised that they may have to try alternate codes if the one they prefer is rejected as a subset. Other typical reasons for code rejection are covered in the troubleshooting section at the end of the manual.
4.5 DELETING CODES
Any code can be deleted by “calling it up” and hitting the Bell key rather than entering a new code (which would over-write the old one). Alternately, if you don’t hit the Bell key but don’t enter a new code, the unit will time out and still delete the code.
To delete the Hard code, press the “Hard Code” button on the CPU board, confirm that you are in hard program mode (slow yellow flash) and press the Bell key or wait 30 seconds.
To delete the Program code, put the unit into program mode (fast yellow flash) from the “Prgm Code” button or from the existing Program code. Enter 0-0 and press the Bell key or wait five seconds. You’ll see the two red confirmation flashes. You’ll need to then press the Bell key again to exit program mode or wait 30 seconds. Note that it can be considered logical to operate without a Program code. It is more difficult to put the unit into program mode (it can only be done from the “Prgm Code” button in the CPU board) but User codes can still be changed and some users may feel that this is a more secure code changing procedure.
To delete any individual User code, put the unit into program mode (fast yellow flash) from the “Prgm Code” button or from the existing Program code. Enter the prefix for the code you wish to delete (01 - 59) and press the Bell key or wait five seconds. You’ll see the two red flashes. You’ll then need to press the Bell key again to exit program mode or wait 30 seconds.
An alternate method to delete any individual User code when you know the actual code but not the two digit prefix is as follows. Put the unit into program mode (fast yellow flash) from the “Prgm Code” button or from the existing Program code. Enter 7-9 followed immediately by the complete code you wish to delete. If it’s a seven digit code you’ll immediately see the two red confirmation flashes. Otherwise press the Bell key or wait five seconds. If you get the single red error flash, it is probably because the code you thought was in memory was not. You’ll then need to press the Bell key again to exit program mode or wait 30 seconds.