Installing a Wiegand Reader to the DC20

In this article, we will discuss the Wiegand standard and how you can install them onto the DC20.

• What is Wiegand?
• Wiegand Protocol 
• Wiring a Wiegand Reader to the DC20
• Set up in Rhombus Console
• Delete a Wiegand Reader
• Helpful Links
• Contact Support or Sales

What is Wiegand?

Wiegand is a wiring standard built in the 1980s by John R. Wiegand. It is used to connect a card swipe action to an access control system. When a card is swiped or presented to the reader, the protocol generates a unique binary code representing the card's ID or other relevant information. Credentials associated with the card are then sent to the controller, which compares the credentials against a database of assigned access permissions. 

In the Wiegand protocol, data is transmitted in the form of binary bits (0s and 1s) using two separate wires, Data0, and Data1 (also referred to as D0 and D1). In an idle state, both D0 and D1 are pulled high (usually +5 VDC). When a 0 is sent, the D0 wire is pulled to a low voltage while the D1 wire stays at a high voltage. When a 1 is sent, the DATA1 wire is pulled to a low voltage while D0 stays at a high voltage.

Wiegand Protocol

The Wiegand protocol has one parity bit, 8 bits of facility code, 16 bits of ID code, and a trailing parity bit for a total of 26 bits. The first parity bit is calculated from the first 12 bits of the code, and the trailing parity bit from the last 12 bits. 

Wiring a Wiegand Reader to the DC20

• D0 (DATA0): yellow wire, minimum 24 AWG, 300 ft max run.
• D1 (DATA1): light blue wire, 24 AWG, 300 ft max run.
• GND: black wire, solid or stranded, twisted pair, minimum 24 AWG, 300 ft max run.
• +12V: red wire, the 12VDC reader power supplies are rated to 660mA each.
• Terminals [OUT1] and [OUT2] are configurable in Rhombus Console to support LEDs and buzzers.

*NOTE: We recommend you consult the appropriate federal, state, and local authorities for any relevant regulations at the time of installation. 

Location of Wiegand ports on the controller:

General Wiegand port wiring configuration:

Set up in the Rhombus Console

1. Navigate to "Settings" and select "Door Controllers" and then click on the controller you wish to configure.

2. Click "Quick Add" or "Configure" in the "Wiegand Ports" section. Ensure you are configuring the number port that corresponds to the physical number port that the reader is connected to on the DC20. We offer the ability to check if there is a Red or Green LED connected. Note: The Rhombus web console does not auto-recognize Wiegand readers, so they will have to be manually added.

Delete a Wiegand Reader

Helpful Links

• Wiegand vs OSDP
• DC20 Overview
• Installing/Registering the DC20

Contact Support or Sales

Have more questions? Contact Rhombus Support at +1 (877) 746-6797 option 2 or support@rhombus.com.

Interested in learning more? Contact Rhombus Sales at +1 (877) 746-6797 option 1 or sales@rhombus.com.