Product Overview
The Allen-Bradley 1746-NO4V is a four-channel analog output module designed for the SLC 500 programmable logic controller (PLC) platform. It delivers precise voltage signals ranging from -10 to +10 VDC, making it an essential component for applications that require accurate analog control, such as valve positioning, variable speed drive references, and process setpoint control. As part of the Allen-Bradley SLC 500 family, the 1746-NO4V integrates seamlessly into both fixed and modular SLC 500 chassis, providing reliable, repeatable performance in demanding industrial environments.
Technical Specifications
Below are the key technical specifications for the Allen-Bradley 1746-NO4V, sourced directly from the manufacturer's documentation.
| Specification |
Value |
| Manufacturer |
Rockwell Automation |
| Brand |
Allen-Bradley |
| Part Number / Catalog No. |
1746-NO4V |
| Series |
SLC 500 |
| Module Type |
Analog Output Module |
| Number of Outputs |
4 |
| Output Voltage Range |
-10 to +10 VDC |
| Full Scale Output |
10 VDC |
| Resolution |
14 bits |
| Conversion Method |
R-2R Ladder |
| Voltage Output Coding |
-32,768 to +32,764 |
| Update Time |
512 microseconds |
| Step Response |
2.5 milliseconds |
| Backplane Current (5 Volts) |
55 milliamps |
| Backplane Current (24 Volts) |
145 milliamps |
| Indicators |
LEDs |
| Ambient Operating Temperature |
0 to 60 degrees Celsius |
| UPC |
10662073735929 |
Key Features & Benefits
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Four Isolated Outputs: The 1746-NO4V provides four independent voltage outputs, allowing you to control multiple devices from a single module.
-
High Resolution: With 14-bit resolution, the module delivers fine control granularity, ensuring precise analog output for demanding applications.
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Fast Update Time: A 512-microsecond update time ensures responsive performance, critical for real-time control loops.
-
Rugged Design: The module operates reliably in ambient temperatures from 0 to 60 °C, making it suitable for harsh industrial settings.
-
LED Indicators: Front-panel LEDs provide immediate status feedback, simplifying diagnostics and troubleshooting.
Real-World Applications
The Allen-Bradley 1746-NO4V is widely used in manufacturing, process control, and material handling systems. Common applications include:
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PID Loop Control: Assign the analog output to a PID controller output to precisely regulate temperature, pressure, or flow.
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Motor Speed Reference: Provide a -10 to +10 VDC signal to variable frequency drives (VFDs) for accurate speed control.
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Valve Positioning: Drive electro-pneumatic or electro-hydraulic positioners in process lines.
-
Data Re-transmission: Send analog signals to recorders, SCADA systems, or other monitoring devices for data logging and analysis.
Installation & Setup Guidance
Proper installation is critical for optimal performance. Follow these guidelines when mounting the 1746-NO4V:
- Mount the module in a 1746 chassis, preferably away from high-voltage AC wiring and the system power supply to minimize electrical noise.
- For ambient temperature considerations, install the module in the chassis nearest to the enclosure bottom.
- Use the removable terminal block (RTB) for wiring. Recommended wire size is #14 AWG maximum, and no more than two wires should be terminated in the same terminal.
- If using an external 24 VDC power supply, activate SW1 external. Alternatively, if backplane power is sufficient, you can use it as the power source.
- Never remove the module while power is applied. Always power down before installation or removal to prevent electrical arcs and damage.
Maintenance & Reliability
To ensure long-term reliability, follow these maintenance practices:
- Periodically inspect the terminal block connections for tightness and signs of corrosion.
- Keep the module clean and free from dust and debris that could affect heat dissipation.
- Monitor the ambient temperature to ensure it stays within the 0 to 60 °C operating range.
- Check the LED indicators for normal status; any unexpected behavior may indicate a wiring or configuration issue.
By following these simple steps, you can maximize the service life of your 1746-NO4V and reduce unplanned downtime.
Compatibility & Integration
The 1746-NO4V is designed for the SLC 500 series of programmable logic controllers. It is compatible with both fixed and modular SLC 500 hardware. The module communicates with the CPU over the backplane, and its output data is updated every 512 microseconds. It uses a 16-bit two's complement binary communication format, ensuring straightforward integration with existing SLC 500 programs.
Buying Guide & Selection Advice
Before purchasing the Allen-Bradley 1746-NO4V, verify that your system has an available slot in the SLC 500 chassis and that the backplane current requirements (55 mA at 5 VDC, 145 mA at 24 VDC) are within your power supply capacity. PLC Source PRO offers genuine Allen-Bradley 1746-NO4V modules with fast shipping and competitive pricing. When ordering, confirm the part number and check for any applicable accessories, such as spare terminal blocks or wiring kits, to ensure you have everything needed for installation.