Visual Test Shell (VTS): Overview & Features
This article describes the Visual Test Shell (VTS), a BACnet testing and diagnostics tool. It covers key concepts, user interface elements, available features, and common tasks supported by VTS.
For task-specific procedures, such as testing BACnet MS/TP devices, see Testing BACnet MS/TP Devices with Visual Test Shell.
The Visual Test Shell (VTS) is a free, open-source software application used to test BACnet protocol implementations in building automation systems. It is primarily intended for engineers, developers, and system integrators who need to validate BACnet device behavior at the protocol and service level.
VTS operates as a protocol-level test and analysis tool rather than as a supervisory control or visualization platform. It allows users to observe, generate, and respond to BACnet messages directly, making it suitable for functional testing, interoperability checks, and troubleshooting.
Core Capabilities
According to the VTS documentation, the application can generate BACnet-compliant service messages, detect and decode BACnet service messages on the network, and execute scripts that generate, receive, and respond to BACnet messages. These capabilities allow users to exercise specific BACnet services and verify device responses under controlled conditions.
VTS is commonly used during development and testing of BACnet devices to confirm correct handling of services such as Who-Is/I-Am, ReadProperty, WriteProperty, and other standard BACnet interactions. Because messages are constructed explicitly, VTS can expose edge cases that may not be visible when testing through higher-level tools.
Project and Availability
The Visual Test Shell project is hosted as an open-source initiative. Project information, source code, and documentation are available from the project home page:
Installation packages and release files can be downloaded from:
http://sourceforge.net/projects/vts/
At the time this article was written, the referenced version of VTS was 3.5.5. Users should consult the project download page to confirm the most recent available release.
Role in BACnet Testing
VTS is listed by BACnet Testing Laboratories (BTL) and BACnet.org as a useful open-source tool for testing BACnet implementations. It is often used alongside conformance testing, device development, and interoperability validation activities.
Because VTS works directly with BACnet protocol services, it is best suited for users who already have a working understanding of BACnet objects, properties, and services. It is not intended as a replacement for commissioning or operational tools used by field technicians.
Support and Community Resources
Community support, discussions, and historical guidance for VTS are available through the project forums hosted on SourceForge:
http://sourceforge.net/projects/vts/forums/forum/86056
As with many open-source tools, documentation and support are community-driven, and users may need to reference source code or BACnet standards documentation for advanced use cases.