Chapter 1 Routing Signals with Your NI2501/2503
NI 2501/2503 User Manual 1-10
©
National Instruments Corporation
Contact Protection
Caution When inductive loads are connected to the relays, a large counter electromotive
force may occur at relay switching time due to the energy stored in the inductive
load. These flyback voltages can severely damage the relay contacts and greatly
shorten the life of the relay.
It is best to limit flyback voltages at your inductive load by installing a flyback
diode for DC loads or a movistor for AC loads.
Terminal Blocks
Several terminal blocks with screw terminals are available for easy signal
connection to the NI 2501/2503 inputs. Refer to Appendix B, Accessories.
Software Choices
You have several options to choose from when programming your National
Instruments switch card. You can use the NI-SWITCH driver software, or
National Instruments application software.

NI-SWITCH Driver Software

The NI-SWITCH instrument driver is an Intelligent Virtual Instrument
(IVI) compliant instrument driver that is bundled with NI-SWITCH cards
at no cost.
NI-SWITCH features a set of operations and attributes that exercise all
the f unctionality of the switch ing hardware, including configuration,
opening/closing, and scanning. In addition, NI-SWITCH comes with
an interactive soft front panel and online documentation.
NI-SWITCH eliminates the need to understand complex register
programming and interrupt handling in the Microsoft operating systems,
and frees you to focus on creating your test system.
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