Product Summary
The Allen-Bradley 1746-NO4I provides four precise current output channels for your SLC 500 system. This module delivers a 0 to +20 mA signal range with 14-bit resolution. It is factory-calibrated and features an open enclosure design. The module includes a removable terminal block for simplified wiring and quick replacement.
Expert Technical Evaluation & Performance Review
The 1746-NO4I uses an R-2R ladder conversion method for its 14-bit resolution. This approach ensures stable and accurate analog output signals. The module achieves a full-scale accuracy drift of only +/- 70 ppm per degree Celsius. This performance guarantees reliable operation across its ambient temperature range of 0 to 60 degrees Celsius.
Each of the four output channels supports a load range from 0 to 500 ohms. The maximum load reactance is 100 µH, ensuring compatibility with most field devices. The module provides an overrange capability of 5%, extending the output to 0 to +21 mA minus 1 LSB. This feature allows for diagnostic and calibration routines without signal clipping.
The step response time for the 1746-NO4I is 2.5 milliseconds at 95%. The update time for all channels in parallel is only 512 microseconds. These fast response times make the module ideal for closed-loop PID control applications. The analog output can directly represent the Control Output (CO) from a PID loop.
For wiring, you must use shielded communication cable like Belden 8761. Keep cable lengths as short as possible to maintain signal integrity. The module draws 55 milliamps at 5 Volts DC from the backplane. It also requires 195 milliamps at 24 Volts DC for its internal circuitry.
The module includes an embedded selector switch for the power supply source. You can choose internal backplane power or an external 24 VDC supply. The external supply must be 24 Volts DC +/- 10% at 195 mA maximum. This flexibility helps in applications where backplane power is insufficient.
The 1746-NO4I uses a 16-bit 2’s complementary binary format for output coding. The output coding range spans from 0 to +32764. This coding scheme provides fine granularity for precise current control. The backplane isolation is rated at 500 Volts DC, protecting your system from ground loops.
Logistics & Standard Packaging Details
- One Allen-Bradley 1746-NO4I Analog Output Module
- One Removable Terminal Block for wiring convenience
- Product documentation and installation guide
We ship all orders via express delivery services. You can select FedEx, UPS, or DHL at checkout for fast shipping.
