Skip to content

2 Ports Serial RS232/RS485 to Ethernet Converter USR-N520-MQTT

Marsoni M251S
Sale price$139.00
Pay 4 payments of $34.75 a month.Shop Pay
Get it in 3 business days with 1 day shipping. Friday, May 29
2 Ports Serial RS232/RS485 to Ethernet Converter USR-N520-MQTT2 Ports Serial RS232 RS485 to Ethernet Converter USR N520 MQTT USR N520 is 2 serial Port RS232 RS485 Secure Serial Device Server which can connect RS 232 485 serial devices to the TCP IP network. It supports bi directional communication. Independent 2 serial ports.(3 in 1 serial port RS232 RS485 RS422 Optional) 5 36V wide voltage input. Modbus RTU to Modbus TCP, Modbus Polling, Modbus to JSON Flow control CTS RTS, XON XOFF Secure Client Operation
Easy Shipping

Quick Dispatch:

Your 2 Ports Serial RS232/RS485 to Ethernet Converter USR-N520-MQTT orders ship within 1-2 business days.

Delivery Options:

  • Standard: 3-7 business days
  • Fast: 2-3 business days
  • Express: 1-2 business days

Order Tracking:

You'll receive a tracking link by email once your 2 Ports Serial RS232/RS485 to Ethernet Converter USR-N520-MQTT ships.

Need Help?
Questions about 2 Ports Serial RS232/RS485 to Ethernet Converter USR-N520-MQTT, sizing, or delivery? We're just an email away.

Live Shipping Estimates:
Enter your location at checkout to see available shipping methods and costs for 2 Ports Serial RS232/RS485 to Ethernet Converter USR-N520-MQTT in your area.

Get Shipping Estimates

Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
4.9 ★★★★★
Based on 809 reviews
Sort
Highest Rating
Newest First
Oldest First
Product Reviews
S
Verified Purchase
Shannon
Dallas, US
★★★★★ 5
Taste like Strawberry
These are large pills but they taste so good! I fall asleep quickly and never wake up foggy.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on February 11, 2026
B
Verified Purchase
B J Thompson
Charlottesville, US
★★★★★ 5
Nice!!!
Dr recommended the supplement is used daily for sleep.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on October 31, 2025
M
Verified Purchase
Mark
Lowell, US
★★★★★ 5
Helps sleep
Works as expected
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on November 6, 2025
A
Amazon Customer
Draper, US
★★★★★ 5
Good Taste. A little slow to Dissolve
I usually take melatonin in gummies form, but these are much more affordable. The take a bit of time to dissolve, so I sometimes end up chewing them, but they have a decent taste, so that is not an unpleasant experience. They seem to work good as other brands/formulations I have tried. I would order these again
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on December 24, 2025
L
Verified Purchase
Lawrence W. Shipway
Lowell, US
★★★★★ 5
Virus Protection
Size: 180 Count (Pack of 1)
Elderberry keeps immune system strong and I have not had cold or flu in over 20 years since I started taking 1 a day. Great prevention
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 8, 2026

recommand products