APC ProtectNet Standalone Surge Protector for Serial RS232 Lines

The APC PS9-DTE is a surge protection module designed for RS232 serial lines. It plugs directly into a DB-9 port, creating a protective barrier that keeps voltage spikes from reaching communication circuits and connected equipment.

This unit fits well in any setting where serial links still matter. Technicians use it behind laboratory instruments, building-automation controllers, point-of-sale terminals, and legacy industrial machines that need uninterrupted data flow. Because it draws no power and adds little weight, you can install it at a workstation, inside a service cart, or out in the field without changing existing cabling habits.

The protector supports one to nine data lines and reacts within 1 nanosecond when a surge appears. It safely diverts up to 0.2 kiloampere of peak current to ground, reducing the stress on sensitive hardware. Compliance with the UL 497B safety standard provides additional assurance for facilities that follow strict electrical codes.

APC includes both a male and a female 9-pin connector, so the module sits in line without extra adapters. The housing remains compact at 2.99 by 1.42 by 0.59 inches, and the device operates in temperatures from 5 to 113 degrees Fahrenheit. A limited lifetime warranty and a user manual complete the package, giving peace of mind long after installation.

Highlights:

• Installs on a DB-9 serial port to block surges traveling through RS232 cables
• Compatible with one to nine data lines
• Responds to a surge within 1 nanosecond
• Handles peak currents up to 0.2 kiloampere
• Supplied with one DB-9 male connector and one DB-9 female connector
• Meets the UL 497B surge protection standard
• Compact housing measures 2.99 by 1.42 by 0.59 inches
• Operates in ambient temperatures from 5 to 113 degrees Fahrenheit
• No rack mounting or external power required
• Backed by a limited lifetime warranty and includes a user manual