National Instruments 779474-01

The National Instruments part number 779474-01 designates the SCC-CTR01 Isolated Counter/Timer Module, designed to serve as an isolation solution for general-purpose timers and counters on data acquisition (DAQ) devices. This module features two input channels capable of handling any input waveform, with a maximum input frequency of 400 kHz and a minimum pulse width of 1 µs. It supports an input voltage range of up to 48 VDC and is equipped with reverse and overvoltage protection rated at ±60 VDC. The isolated inputs are limited to a maximum current of 10 mA within the specified operational temperature range. The module operates with a propagation delay of 180 ns when transitioning from LOW to HIGH and 150 ns from HIGH to LOW for a 5V input signal.

In addition, the 779474-01 includes a single output channel that accommodates a load voltage range of 5 to 48 VDC, maintaining the same maximum output frequency and minimum output pulse width as the inputs. It features maximum switching current of 100 mA and inrush current of 600 mA, along with integrated protection that disables the output in the event of a short circuit, allowing automatic recovery once the fault is removed. The output, as well as the Vdd pins, are also protected against reverse and overvoltage conditions up to ±60 VDC.

Physical dimensions of the module are 3.50 in. × 1.15 in. × 0.73 in., with a weight of 1.0 oz. It is fitted with a 20-pin right-angle male connector and a 7-pin screw terminal for I/O interfacing, suitable for wire gauges ranging from 28 to 16 AWG. The module requires a maximum digital power of 140 mW when connected to a +5V rail. It is recommended for operation within a temperature range of 0 to 50 °C, relative humidity of 10 to 90% RH, and can be stored in a temperature range of –20 to 70 °C. The maximum operating altitude is capped at 2000 m.