APC PS9-DTE ProtectNet RS-232 DTE Serial Port Surge Protector DB9 Lines 1-9

APC PS9-DTE ProtectNet RS-232 DTE Serial Port Surge Protector DB9 Lines 1-9

The APC PS9-DTE ProtectNet is a standalone inline surge protector designed to safeguard RS-232 DTE serial communication lines. It connects directly between a host device and a peripheral, passing data signals through while shunting transient voltage spikes that could damage sensitive serial port circuitry. The pass-through DB9 male-to-female design requires no external power and adds no cabling to the installation.

Specifications & What's Included

• Part Number: PS9-DTE
• Interface: RS-232 / EIA-232 serial
• Configuration: DTE (Data Terminal Equipment)
• Connector: DB9 female input — DB9 male output (inline pass-through)
• Lines Protected: 1 through 9 (all signal lines)
• Form Factor: Inline adapter with red thumbscrew retention hardware on both ends
• Unit only — no cables or packaging included

Applications

RS-232 serial lines are used extensively in industrial automation, point-of-sale systems, laboratory instruments, legacy computer peripherals, and telecom equipment. Serial ports are particularly vulnerable to voltage transients caused by nearby lightning strikes, power switching events, or ground potential differences between connected equipment. The PS9-DTE installs at the DTE device end — typically a computer, terminal, or controller — to protect the host port from surges arriving via the serial cable. It is a standard precaution in environments where serial equipment runs across longer cable runs, between buildings, or alongside other electrical systems. APC introduced the ProtectNet series to address exactly this need, offering protection that is passive, transparent to the data signal, and requires no configuration.