Assa DK-26 manual PROBLEM-- How to check the Keypad

Page 30

Rev. A.2, 10/03

Page-v

PROBLEM-- How to check the Keypad

For reference, when each key is pressed, two terminals will measure zero volts with respect to the WHT (common) terminal. You can use a voltmeter to see that each key is working correctly. Put the positive probe on WHT and when key #1 is pressed you will read roughly zero volts on VIO and BRN (the other terminals in the matrix will be reading about 11 volts. The terminal pair that will show zero volts for the other keys are as follows:

#2 = VIO + GRY #7 = ORG + BRN

#3 = VIO + BLK #8 = ORG + GRY

#4 = PNK + BRN #9 = ORG + BLK

#5 = PNK + GRY #0 = BGE + GRY

#6 = PNK + BLK BELL=BGE +BLK

PROBLEM-- Unusual operation complained of after some operating history

"Unusual" operation can be caused by the microprocessor in the CPU Board being disturbed by electrical noise. Symptoms can vary quite a bit. The unit may forget its codes, the action of the keypad beeper may become drawn out or erratic, the timer may function at widely varying ranges, etc. To cure the problem, remove power from the CPU Board for about 10 seconds, then reconnect it. This forces the microprocessor to reset itself and reload its program. If the unit has functioned for a long period of time without incident, this may be an adequate fix. The problem may never reoccur and the end user should be made aware of this simple fix if it should reoccur. All microprocessors can sometimes "crash" and they are restored by reset. If, however, the problem is more persistent, steps can be taken to guard against electrical noise problems. You should make sure that the MOV furnished with the unit is properly installed across the electric lock (review Figures 3-5). The inductive kickback from electric locks can often be a source of considerable electrical noise. Noise can also come from the keypad cable, particularly if its length has been extended. There is no specific distance which is a limit for an extended keypad cable. Shorter is always better as cable noise varies with the proximity of noise producing devices such as motors, fluorescent or neon lighting etc. The same problem can occur if the cable from an exit switch is extended a long way from the CPU board. If there are noise sources, it may be necessary to limit the cable run distances while also trying to avoid the noise sources.

If the problem shows up frequently, it is usually bad power. This particularly occurs when a fail secure lock is operated from the same supply as the DK-26. When the lock is energized, it may draw too much power for the power source. This reduces the voltage and these voltage swings can crash the microprocessor. The solution is either to use a power supply with greater capacity or use two power supplies: one to operate the DK-26 and the second to operate the fail secure lock through the DK-26's lock control relay.

IF THE PROBLEM PERSISTS

CALL SECURITRON TOLL FREE: 1-800-MAG-LOCK

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Contents Connecting the Keypad Cable to the CPU Board Adding Other Lock Control SwitchesSetting the Time Range and Toggle Mode 1 Changing the User and PROG. Code from Keypad --PageWiring with Touch Sense BAR and Magnalock Nightlight FunctionPhysical Installation Physical Installation of Keypad DK-26 Power Consumption Volts WiringPower Selection Power and Electric Lock WiringOverview of CPU Board AC Lock AC Power Wiring DC Lock with AC PowerDC Lock AC Power Wiring DC Lock with DC PowerDC Lock DC Power Wiring Adding Other Lock Control SwitchesUSE of the F Terminal Adding External Contacts for Fail Safe and Fail Secure Locks REX FunctionDouble Break Wiring for Free Egress TWO Pole Switch Programming Fixed ProgrammingRev. A.2, 10/03 Page-11 Keypad Changeable Programming Changing the User and Program Code from the Keypad Adding Multiple User Codes Masterkey USE of the Hard CodeSubset Codes Deleting CodesChanging LED and Beeper Operation USE of the Programmable Relay Doorbell FunctionDuress Function ANTI-TAMPER Alarm Function Door Prop Alarm FunctionNightlight Function Additional Hard Wired OptionsHardwired Code Disabling Dual PAD OperationAlarm System Shunting Wiring to Shunt Alarm System on DoorANTI-TAILGATING Wiring with Securitrons Touch Sense BAR and Magnalock Wiring of DK-26, Touch Sense BAR and MagnalockMAGNACARE→ Limited Lifetime Warranty Appendix a Command Summary With the Unit in Program Mode Fast Yellow Flash Rev. A.2, 10/03 Page-ii PROBLEM-- a key isn’t echoed no beep or LED flash PROBLEM-- Door opens on a short code that wasn’t programmed PROBLEM-- How to check the Keypad
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