X20BB81 selection record: single-slot expandable bus base and installed-system fit
X20BB81 belongs to the B&R X20 automation system. Specify X20BB81 by its complete designation and documented role; the visible similarity of two modules is not a compatibility decision.
Identification matrix
| Technical item | Verified value / selection note |
|---|---|
| Complete designation | X20BB81 |
| Base role | Bus controller and supply |
| Expansion | One X20 add-on slot |
| Included | Left and right end cover plates |
The values above identify X20BB81 at catalog level. Verify the installed revision, label and current manufacturer manual before issuing a purchase order or approving a design change.
01 / Intended duty
For X20BB81, Use this base when the bus station requires exactly one add-on interface or hub module beside its controller and supply.
Capture the actual cabinet location, connected equipment, expected operating range and the consequence of a lost signal or network connection. These details turn the X20BB81 code into a specific engineering requirement.
02 / Fit boundary
When replacing or adding X20BB81, The X20BB80 does not provide this additional slot. Confirm module width, connector positions and the complete power arrangement.
Check X20BB81 against the as-built wiring, X20 base, terminal block, supply module and controller software. Keep every accessory and revision difference visible in the RFQ; do not approve a look-alike solely from a photograph.
03 / Acceptance record
For commissioning X20BB81, Verify that all three modules seat correctly, the add-on interface is recognized and the station powers up without faults.
Record date, test conditions, observed LEDs or diagnostics and as-left configuration for X20BB81. Restore normal control after testing and obtain the site's electrical or safety sign-off where required.
Code alternatives and exclusions
The references below, if any, share a relevant X20BB81 code stem or functional family. Their ratings, ports, wiring or software may differ; they are not automatic replacements.
No additional exact-stem variant is assigned to X20BB81 here; seek written manufacturer confirmation for any alternative.
Purchase handover
Quote X20BB81 exactly, with quantity, required delivery, existing hardware revision and a readable label photograph. Attach the application drawing and network or channel map so the supplier can confirm the right product and accessories.
The buyer should retain a written fit decision for X20BB81, and maintenance should keep the final settings and test evidence. Do not energize a replacement until the approved checks are complete.
