A breakout box is a piece of electrical test equipment used to support integration testing, expedite maintenance, and streamline the troubleshooting process at the system, subsystem, and component level by simplifying the access to test signals. Breakout boxes span a wide spectrum of functionality. Some serve to break out every signal connection coming into a unit while others breakout only specific signals commonly monitored for either testing or troubleshooting purposes. Some have electrical connectors and others have optical fiber connectors. A breakout box serves as a troubleshooting tool to determine the wiring of an electrical connector interface on a networking device or computer. Typically, a breakout box is inserted between two electrical devices to determine which signal or power interconnects are active. Breakout boxes are extremely useful in troubleshooting connection problems resulting from manufacturing errors or defective interconnects resulting from broken wiring. Breakout boxes are specific examples of a more general category of network testing equipment called "status monitors". Various such monitoring devices are available for testing serial interfaces, including RS-232, RS-449, V.35, and X.21, as well as specialty interfaces. They generally come with several kinds of connectors and are quick and easy to use for isolating problems with serial transmission connections in networking, telecommunications, and industrial settings.
Variants
The term breakout box is derived from the mechanical enclosure in which a connector's aggregate connections are separated into individual signal or current carrying wires or cables. Often, if there are only a few connections, then a breakout cable may be used, as is common on notebook computers. The most common breakout boxes use D-subminiature connectors and are configured with both male and femaleDE-9, DA-15, DB-25, DC-37 or DD-50 standard density connectors and related test points. These units can also be used to simulate special cables, interconnect RS-232 devices, or adapt test equipment to an RS-232 device.
Breakout boxes for post-production studio editing suites. Breakout boxes are used to patch audio/video output signals from multiple sources and connect them to other devices quickly. These boxes range from simple analog audio interconnects with up to 96 audio ins/outs to complex plug-in component with composite video, S-Video, HDMI, RS422 control, and digital signaling.
Industrial I/O breakout box. A piece of electronic test equipment used for diagnosing problems in computer communications, typically over a serial port. The breakout box sits between two pieces of equipment and usually has some LEDs to display the status of the different signals in the serial cable. It will also often have DIP switchesto let the user connect or disconnect different signals in the cable, and it will usually have connector pins that let the user short pins together using electrical jumpers, or gain access to individual signal lines with an oscilloscope or other test equipment.
RS-232 breakout box: Typically, RS-232 breakout boxes offer complete control of RS-232 interface, test, re-wire and open signal lines. These devices are pocket-sized for circuit testing, monitoring and patching. The usually provide 10 interface signal powered LEDs to permanently monitor TD, RD, RTS, CTS, DSR, CD, TC, RC, DTR TC signals, as well as enabling the breakout of individual circuits or reconfiguration or patching any or all of the 24 active switch positions.
Docking stations for notebook computers. These draw the signal for multiple connectors from the pins of one connector.
Electronic control units in automotive engines have proprietary connectors that are densely packed, environmentally sealed and difficult to gain access to without causing damage. The manufacturer sometimes provides a breakout box to allow service engineers to test the unit.
