SDC-620 Multiple door controller
9
Copyright© 2016
– Saflec Systems (Pty) Ltd.
http://www.saflecsystems.co.za
Important:
When driving inductive loads such as strike locks, care should be taken to prevent a
back-EMF voltage spike. In order to do this a freewheeling diode (also known as flyback diode)
should be connected across the load as seen in the figure below.
Figure 15
Diagram showing freewheeling diode over an internally powered inductive load (eg. strike lock)
– normally open.
Step 8: Connect the Wiegand devices
The Wiegand devices communicate with the SDC-620 via five signalling lines.
These lines can be broken into two groups:
The data lines (Data 0, Data 1)
The control lines (Red LED, Green LED and Buzzer)
Note:
Make sure that the power is switched off before connecting these cables.
Connect the data and control lines ensuring that the correct cables are used.
Connect the power to the Wiegand device.
Figure 16
Wiring configuration for the Wiegand interfaces
The second Wiegand interface can also be wired up in the same way.
NOTE: In the SACS software the two Wiegand readers should be configured to be remote
address 0, reader 1 and 2. This means that remote address 0 is shared between the RS-485
slave devices and the Wiegand port.
