Many Control Modes Including Rheostat Mode
To accommodate a variety of DC sources, all ARx Series MagnaLOADs come with several distinct control modes, including: Voltage Mode, Current Mode, Power Mode, Resistance Mode, Shunt Regulator Mode, and Rheostat Mode. Preference for DC regulation is given to the parameter in the selected mode within the programmed set-points. Using the MagnaLOAD's set-points and trip settings, the product can configured to either trip with a fault when a limit is exceeded or to cross-over into a different regulation state.
Shunt Regulator Mode turns the MagnaLOAD into a high-speed smart braking resistor, engaging the DC input only when a specified voltage is exceeded by a user-defined percentage, while limiting the shunt current to a programmed set-point.
Rheostat Mode, unique to the ARx and WRx Series, bypasses the digital controls to provide direct control of the MagnaLOAD's internal resistor network. Using this mode, true resistance step load response can be achieved without the traditional bandwidth limitations. While the standard operating modes offer 16-bit programming resolution, Rheostat Mode provides 31 different resistor states.
Extensive Programming Support
All ARx Series MagnaLOADs come with a dedicated National Instruments LabVIEW™ driver, Interchangeable Virtual Instrument (IVI) driver, and support for a wide range of Standard Commands for Programmable Instrumentation (SCPI). These programming interfaces support full control, measurement, and monitoring of the MagnaLOAD. All of the MagnaLOAD's available communication interfaces are supported by these drivers and command sets, including: USB, RS485, LXI TCP/IP Ethernet, and IEEE-488 GPIB.
Showcased in the following basic code examples, SCPI commands provide the simplest form of communication by using plain ASCII text and parameters sent over a basic socket connection. Over 50 commands are provided, with detailed documentation in the ARx Series User Manual.