USB to Serial RS232 4 Port Adapter - Wall Mount DIN Rail

In this review of the USB to Serial RS232 4 Port Adapter, the reviewer finds it best suited for engineers, field technicians, and industrial integrators who need a rugged, compact way to convert a single USB connection into multiple DB9 serial ports. The single biggest reason to buy is its combination of a metal enclosure and flexible mounting options, which deliver reliable serial connectivity in harsh environments without extra power supplies. Installation is straightforward and the device keeps COM assignments stable, making it practical for equipment that must remain reachable after reboots.

Key Features

• Industrial strength: The rugged all-metal enclosure provides durability and protection for deployments in demanding industrial settings.
• Four RS232 ports: Converts one USB connection into four DB9 serial ports to connect multiple legacy devices simultaneously.
• COM retention: Maintains assigned COM port numbers so ports are automatically reassigned after reboots, reducing configuration time.
• USB powered: Runs from an available USB port so no external power adapter is required, simplifying installations on-site.
• Versatile mounting: Integrated wall-mount brackets and included DIN rail clips allow secure mounting in control cabinets or on a desk.

Who It's For

The adapter is ideal for technicians who manage serial equipment like PLCs, sensors, field data loggers and communication gateways that require reliable RS232 ports in industrial racks or outdoor enclosures. Its metal housing and DIN rail compatibility make it a natural choice for factory floors and network closets where sturdiness matters.

Those who primarily need sequential port numbering for simple desktop experiments may find occasional quirks in port mapping a minor annoyance, so users requiring strict numeric sequencing for short-term lab use should consider that. For most production and field deployments the COM retention and rugged build outweigh this limitation.

Pros & Cons

Pros

• Durable metal enclosure that stands up to industrial conditions.
• Maintains COM port assignments to preserve serial device mappings after reboot.
• No external power needed because it is USB powered, simplifying wiring.
• Flexible mounting options with wall brackets and DIN rail clips included.

Cons

• Port mapping can be non-sequential in some cases, which may require checking COM assignments during setup.
• Limited to RS232 DB9 connectivity only, so additional adapters are needed for other serial standards.

Specifications

Manufacturer	StarTech
Ports	4 x RS232 DB9
Interface	USB to serial (FTDI chipset)
Power	USB powered (no external adapter required)
Mounting	Wall mount brackets and DIN rail clips included
Enclosure	Rugged all-metal construction

Our Verdict

The USB to Serial RS232 4 Port Adapter is a practical, value-oriented choice for industrial and field use where durability and stable COM assignments matter. Buyers who need a compact, USB powered RS232 hub with flexible mounting will find it reliable; those needing other serial standards will require additional converters.

Frequently Asked Questions

Does it require an external power supply?
It is USB powered and does not need an external power adapter for normal operation.

Will it keep the same COM port numbers after a reboot?
Yes, the adapter supports COM retention so assigned port values are maintained across reboots.

Is it suitable for DIN rail installation?
Yes, it ships with top-hat DIN rail clips and also includes wall-mount brackets for flexible installation.