Assa manual Power Selection, DK-26 Power Consumption Volts, Power and Electric Lock Wiring

Rev. A.2, 10/03 Page-3

3. WIRING

3.1 POWER SELECTION

The DK-26 operates on 12 to 24 volts AC or DC. Nearly all electric locks operate on voltage within this range, so the power supply you would normally utilize to operate the electric lock will also operate the DK-26. Power consumption of the DK-26 depends on voltage and is shown on the following chart:

DK-26 POWER CONSUMPTION:	12 VOLTS	24 VOLTS
REST STATE (MIN)	7 mA	20 mA
RELAYS, LED’S, + BEEPER ON (MAX)	160 mA	190 mA

Be sure that your power source is of adequate capacity to operate both the lock and DK-

26.If the installation is "under-powered", the voltage of the supply will drop rapidly when the lock is energized and this can crash the microprocessor.

3.2 CONNECTING THE KEYPAD CABLE TO THE CPU BOARD

There are 12 color coded wires in the keypad cable. Refer to Figure 2 and connect each wire to the indicated terminal on the CPU Board. No other connections may be made to these terminals (except if two keypads are used with one CPU board).

3.3 POWER AND ELECTRIC LOCK WIRING

The wiring scheme for electric lock control varies depending on the type of lock and the desired control. The following sections provide drawings and explanations for different types. One general point is that the DK-26’s lock control relay has 5 Amp contacts. Most electric locks draw much less. If, however, you are using a specialty lock which draws more than 5 Amps or has a higher in-rush current, purchase a high current relay and use the DK-26’s contacts to switch this relay while using its high capacity contacts to switch the lock. Note finally that the DK-26 includes additional options which are covered in Sections 6 and 7. To determine the complete wiring for your installation, begin with the drawings shown in Section 3 and then check Sections 6 and 7 to see if you will require any of the additional features.

3.3.1 AC LOCK WITH AC POWER

This is the simplest installation possible with the DK-26. A fail secure lock operating on AC is used. This is generally an electric strike. “Fail secure” means that the lock is secure when it is not powered. Power is applied to release the lock. Referring to figure 3, select a transformer of the same output voltage as the lock (12 or 24 VAC). Make sure the capacity of the transformer is large enough to operate both the DK-26 and the lock and that the transformer is UL listed under the UL 294 standard (to maintain the DK-26 UL listed status). The two transformer secondary wires connect to the “AC input” terminals as shown (there is no polarity with AC). Power from one terminal then goes to the common of relay #1. The NO contact of relay #1 will power the lock (releasing the door) when a correct code is entered. Note that AC locks are normally all fail secure. If you come across a fail safe AC lock (secure when powered) you would merely make the connection to the lock from the NC1 rather than NO1 terminal.