The Allen-Bradley 1794-OF4I is a FLEX I/O analog module with four isolated analog outputs. It is compatible with several terminal base units, including the 1794-TBT, 1794-TB3, 1794-TB3TS, 1794-TB3S, 1794-TBNF, and 1794-TBN. The module can be mounted on a DIN rail or directly onto a panel. It features an open enclosure and has dimensions of 3.7 x 2.6 x 3.7 inches.

The external DC voltage range for the 1794-OF4I module is 19.2 to 31.2 VDC, including a 5% AC ripple. The module requires an external DC power supply current of 210 mA at 24 VDC. It supports a maximum overload of 30 V or 32 mA continuous on a single channel at a time. The module can handle a maximum current load of 3 mA on the voltage output and a 0 to 750-ohm resistive load on the voltage output. Its output current ranges are 4-20 mA and 0-20 mA, both of which are user-configurable. The output voltage can be set to ±10 V, ±5 V, 0-10 V, or 0-5 V, also user-configurable. Both the voltage and current terminals will have 0 output until the module is properly configured.

The 1794-OF4I has a maximum power dissipation of 4.7 W at 31.2 VDC, with a maximum thermal dissipation of 16 BTU/hour at this voltage. The module's isolation voltage depends on the terminal base unit used. It offers a 250 V continuous isolation rating when connected to a 1794-TBN base unit, and a 120 V continuous isolation rating with other compatible base units. The FlexBus voltage is 5 VDC, and the FlexBus current requirement is 50 mA. The module's resolution is 15 bits plus sign, with a voltage resolution of 0.320 mV/cnt and a current resolution of 0.656 mA/cnt. The update rate for all channels is 2.5 or 5 milliseconds, with a step response of less than 25 µs at 63% of full scale.

Both voltage and current terminals offer an absolute accuracy of 0.1% full scale at 25°C. However, the accuracy drift varies with temperature: 0.0012% full scale per °C for the voltage terminal and 0.0025% full scale per °C for the current terminal. The 1794-OF4I uses digital-to-analog (DAC) conversion, with a resolution of 15 bits plus sign or 0.320 mV/cnt for voltage, and 0.656 mA/cnt for current.

The module provides a signal update rate of 2.5 ms or 5.0 ms for all channels, which can be configured uniformly across all channels. The step response to 63% of full scale is < 25 µs, with a current load on the voltage output of 3 mA. The module is factory calibrated, but it also offers the option for manual calibration if necessary. It can tolerate a maximum overload of 30 V continuous or 32 mA continuous on one channel at a time.

The 1794-OF4I is fully compatible with terminal base units such as the 1794-TB2, 1794-TB3, 1794-TB3S, 1794-TB3T, 1794-TB3TS, and 1794-TBN. It requires a FlexBus voltage of 5 VDC and FlexBus current of 50 mA. The module's external power supply requires a nominal 24 VDC, with an applicable voltage range of 19.2–31.2 VDC.

The 1794-OF4I can be mounted on a DIN rail or directly onto the enclosure sub-panel. It is also compatible with any available Flex I/O communication adapter and is approved for use in hazardous locations.