What B-ACDC Is
A BACnet device profile is a standardized capability level: a checklist of things a device must be able to do before it can wear the label. B-ACDC (BACnet Access Control Door Controller) is defined in Annex L of ANSI/ASHRAE 135-2024 (clause L.7.4) as a device that controls doors, representing each door it manages through an Access Door object.
It is a Miscellaneous-family profile, so a device can claim it alongside a profile from another family. The checklist items are BACnet Interoperability Building Blocks (BIBBs); a device documents its claim in its PICS (Protocol Implementation Conformance Statement).
Where It’s Used
B-ACDC fits the device that operates door hardware in a physical access-control system.
- Door controllers. A device driving lock, strike, and door-position hardware, exposed as Access Door objects.
- Integrated access points. A controller presenting its doors to a building or security system over BACnet.
- Multi-door panels. A panel that manages several doors, one Access Door object each.
Required Services
The table below is the exhaustive service set required by the B-ACDC BIBBs. Initiates means the device sends the request or notification; Executes means the device receives and acts on it (responding, for confirmed services). BIBB codes encode the same split: a -A BIBB is the initiating side, a -B BIBB the executing side. A - means the profile does not require that direction; a device may still support it.
| Capability area | Service | Required by BIBB | Initiates | Executes |
|---|---|---|---|---|
| Data sharing | ReadProperty | DS-RP-B, DS-ACAD-B | - | Yes |
| Data sharing | WriteProperty | DS-WP-B, DS-ACAD-B | - | Yes |
| Device and network management | Who-Is | DM-DDB-B | - | Yes |
| Device and network management | I-Am | DM-DDB-B | Yes | - |
| Device and network management | Who-Has | DM-DOB-B | - | Yes |
| Device and network management | I-Have | DM-DOB-B | Yes | - |
The doors are modeled as hosted objects. The DS-ACAD-B requirement means the device hosts at least one Access Door object, which carries the door’s command and status. Reading and commanding a door is the ReadProperty and WriteProperty surface above; the profile adds no separate door service.
Related Profiles
| Profile | How it differs from B-ACDC |
|---|---|
| B-ACCR | Access Control Credential Reader: reads credentials at a door rather than operating the door hardware |
| B-ACC | Access Control Controller: the full access controller with events, scheduling, and the access decision model |
| B-SA | Smart Actuator: a general commandable output, without the Access Door object model |
What Chipkin Provides
The CAS BACnet Stack implements the Access Door object and the data-sharing and discovery services the B-ACDC profile requires. Talk to us about building or integrating a B-ACDC device on the stack.