Lenel DirecDoor, Installation Manual

Page: 57 / 90

DirecDoor Installation Guide
57
CHAPTER 7
DO Interface
The digital outputs (DO) interface provides six (6) digital outputs rated at 20 mA @ 12 VDC
maximum per output point.
Note the following:
•
The maximum allowable distance from the DirecDoor DO interface and the output device is
1,000 feet (304.80 meters).
•
Two-conductor, 20-AWG shielded, stranded wire is recommended for the DO interface.
Wiring Digital Outputs (DOs)
Digital DOs are obtained by using unassigned reader outputs. When used as DOs, these outputs
require pull up resistors.
1.
Mount the digital output device according to the manufacturer’s specifications.
2.
Complete the wiring.
If the DO is used to energize a relay, install a diode in parallel with the relay coil to absorb
transients when the relay is de-energized. A transient protection diode (user supplied) is
necessary on the DO interface.