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PXI-8421-8
PXI-8421/8, 8-Port, RS-485 Interface
Actual item may vary if no part number is provided on quote request.
✔ 2 Year Warranty Included
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March 2025
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January 2025
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May 2025
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January 2025
Carol Zimme**** Verified Buyer
" Very responsive and helpful, competitive pricing. Good source! "
July 2025
Andrew Gar**** Verified Buyer
" Amazing to work with and had my order within 1 week after purchasing with all NI certs and data that were needed. "
March 2025
Said Sai**** Verified Buyer
" Competent contact for highly specialized components. The support team is very knowledgeable. Many thanks for the help and the fast shipping! "
January 2025
Bob C**** Verified Buyer
" Jason was able to get our emergency situation taken care of quickly and professionally. "
May 2025
Gregg Flecki**** Verified Buyer
" Great service and great products. This is my 2nd time using Apex Waves, truly impressed. "
January 2025
National Instruments PXI-8421/8 RS-485 Interface
The National Instruments PXI-8421/8 is a Serial Interface Module for PXI systems. This module is designed for communicating with RS-422 and RS-485 serial devices. The PXI-8421/8 (Part Number: 777735-08) has 8 ports, whereas this module is also available in 4-port (777735-04) and 2-port (777735-02) versions. This serial interface module is offered with an adaptor cable that can be used for the interconnection of the SCSI 68-pin connector provided on the module and eight standard DB-9 male connectors.
The NI PXI-8421/8 is fully compatible with a standard PC serial port. This module comes with Plug and Play compatibility to provide the user with a switchless configuration experience. With this module, users will be able to connect to various serial devices for test and measurement, laboratory data acquisition, industrial, and various manufacturing applications. This 8-port module also offers RTS/CTS hardware handshake lines and can receive and transmit FIFOs as well. The NI PXI-8421/8 comes equipped with an SCSI 68-pin I/O connector, has 64 Bytes FIFO, and offers a data transfer rate of up to 460.8 kb per second. As far as its power consumption is concerned, the NI PXI-8421/8 consumes 1.1 A of current while operating in typical conditions, and a maximum of 2 A at +5 VDC.
This Serial Interface Module fully supports LabVIEW Real-Time and can be installed and utilized as a standard serial port through existing applications. Moreover, this module can be configured through applications written with NI-VISA development environments, including NI LabVIEW, C++, Excel, LabWindows/CVI, Measurement Studio, etc. This module offers 2,000 V port-to-port isolation for the minimization of troubles such as ground loops.
The NI device measures 3.94 x 6.37 in. in physical dimensions. It has recommended operating and storage temperature ranges of 0 to 55 °C and –20 to 70 °C respectively, non-condensing operating and storage humidity ranges of 10 to 90% RH and 5 to 95% RH. The serial interface module is designed to comply with the following electrical safety standards: IEC 61010-1, EN 61010-1, UL 61010-1, and CSA 61010-1.
PXI-8421/8 Obsolete Status has been announced by National Instruments, but the module will still be available for purchase and repairs by Apex Waves.
| Model | PXI-8421-8 |
|---|---|
| Part Number | 777735-08 |
| Manufacturer | National Instruments |
| Type | PXI Serial Interface Module |
| Ports | 8 |
| Supported Serial Protocols | RS-485/RS-422 |
| Maximum Transfer Rate | 460.8 kb/s |
| Dimensions | 3.94 x 6.37 in. |
| I/O Connector | 68-pin SCSI |
| PXI-8421/8 Manual | User Manual and Maintenance Manual Available for Download |
| Price | Contact a sales representative for a quote. |
Associated part numbers for PXI-8421-8:
National Instruments PXI-8421/8 Frequently Asked Questions
Question: What is the typical current for the PXI-8421/8 at +5 VDC?
Answer: The typical current for the PXI-8421/8 at +5 VDC is 1100 mA.
Question: What is the NI PXI-8421/8 FIFO size?
Answer: The NI PXI-8421/8 FIFO size is 64 Bytes.
Question: What is the maximum current for the PXI-8421/8 device?
Answer: The PXI-8421/8 device has a maximum current of 2000 mA.
PXI-8421-8 PDF Manuals
ARCHIVED--GETTING-STARTED-WITH-YOUR-PXI-SERIAL-HARDWARE-AND-SOFTWARE-FOR-WINDOWS-2000.PDF
ARCHIVED--GETTING-STARTED-WITH-YOUR-PXI-SERIAL-HARDWARE-AND-SOFTWARE-FOR-WINDOWS-ME-9X.PDF
ARCHIVED--GETTING-STARTED-WITH-YOUR-PXI-SERIAL-HARDWARE-AND-SOFTWARE-FOR-WINDOWS-NT.PDF
ARCHIVED--NI-SERIAL-HARDWARE-SPECIFICATIONS-GUIDE.PDF
NI-SERIAL-HARDWARE-SPECIFICATIONS-GUIDE.PDF
NI-SERIAL-LEGACY-HARDWARE-SPECIFICATIONS-AND-FEATURES-GUIDE.PDF
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