National Instruments OP-8935 Analog I/O Module

The National Instruments OP-8935 Analog I/O Module, a versatile switch load signal conditioning (SLSC) module, provides eight analog inputs and eight analog outputs, each having a ±20 V range. The OP-8935's onboard fault insertion capabilities, which are designed to work with PXI or CompactRIO hardware, increase its usefulness in a range of testing and measurement applications. There are a total of 112 relays in the module's fault insertion unit (FIU), or seven relays for each differential pair. It is possible to control each relay separately, which makes comprehensive failure simulation possible. Fault injection using the two user-supplied voltage references (VBusA and VBusB) for each signal, as well as open-circuit and short-circuit situations for the signal pairs, are examples of potential faults.

All relays are open by default, preventing the creation of any unintentional signal paths. In order to avoid possible short circuits, the module's architecture makes sure that VBusA and VBusB cannot be connected to the same channel at the same time. Additionally, only one additional fault (either VBusA or VBusB) is permitted on a channel pair if Signal + and Signal - are shorted together. Because of its careful fault insertion methodology, the OP-8935 is a dependable instrument for demanding testing situations.

The OP-8935's relay technology provides quick response times of less than 0.5 milliseconds along with high density. Nevertheless, this technique is susceptible to peak currents above 5 amps, which may cause the relays to malfunction. Customers are recommended to install resistors to limit peak current in order to reduce this risk, particularly in light of the capacitors at the output that may produce current spikes. These capacitors can result in peak currents that exceed internal restrictions even when the power supply is limited to 0.1A, therefore careful circuit design is required.

An RMA can be sent out for repair if a relay fails in the short mode. Alternatively, a defective relay may only need to be replaced once by a technician who possesses IPC-610 certification and through-hole lead-free soldering knowledge. The OP-8935 is an essential part for testing and validating analog signals in complicated systems because of its built-in protections and strong fault insertion capabilities.