National Instruments GPIB-120A GPIB Expander/Isolator

The NI GPIB-120A (Part Numbers: 776564-01, 776564-02, 776564-03, 776564-04, 776564-05, and 776564-06) is a GPIB Expander/Isolator. The IEEE 488.1 standard allows as many as 15 electrical loads in a GPIB system. Additionally, the GPIB-120A expands the maximum GPIB system devices limit from 15 to 28. This GPIB Expander can also be used in measurement and test systems, since it offers an electrically isolated interface. The GPIB is an interface or link system that is used by interconnected devices to communicate. In this arrangement, interconnected devices communicate through messages that flow across the interface system.

With this model, rewriting user’s application software is not required because this model comes with transparent software. Thus, the user can connect two GPIB systems in a functionally transparent scheme. The GPIB-120A Bus Expander can double the cable limit of 20 meters as well. This GPIB Expander consists of two busses: Bus A and Bus B. Both sides come with identical circuitry and operate in complete isolation from each other. The NI device is equipped with operating and breakdown isolations of 60 V and 1600 V respectively. It is equipped with a standard Amphenol or Cinch series 57 Microribbon or Amp Champ type connector.

The NI GPIB-120A features seven LEDs on the front panel. The state of the Active Controller and System Controller is indicated by a dedicated LED. Bus A and B incorporated in this expander are capable of being appeared as independent GPIB devices. The National Instruments GPIB-120A comes with 16 signal lines and eight shield drain or ground return lines. The 16 signal lines provided can be divided into these three groups: five interface management lines, three handshake lines, and eight data lines. The device has a typical power requirement of 27 VA. It has a typical data transfer rate degradation of 250 ns per byte.

The GPIB-120A is equipped with a case which measures 3.5 x 8.5 x 13.0 inches. The case is made with UL94V-0 flame retardant polystyrene DOW 60875F or Noryl FN-215. It has a recommended operating temperature range of 0° to 45° C, and a non-condensing relative humidity range of 5% to 95%.