RS-232 COM Port Surge Protector, SUG-RS232-2P

SUG-RS232-2P, 2-channel surge protector for RS232, covering signals TX, RX, GND / screen

The SUG-RS232-2P is designed to protect the RS-232 port against overvoltage in PC computers or industrial controllers. It includes 2 protected channels + ground (cable shield), which can be used for RX, TX, and GND (shield) signals. Each signal can be assigned to the terminals of the limiter as desired.

It uses modern solutions in the form of MOSFET fuses, which limit the flow of high surge currents through the limiter, resulting in increased durability and significant reduction of the surge voltage reaching the protected device. An additional advantage of this solution is the limitation of the possibility of equalizing currents between individual devices.

The structure consists of two protective channels with voltage and current limiting stages above 300mA. The product has very low attenuation, making it possible to transmit data at very high speeds.

The signal ground, which also serves as the cable shield, is protected against potential differences with respect to ground and individual transmission wires.

High-quality window terminals with high current load capacity reduce the risk of damage during high surge impulses and temporary current overloads.

The product is designed for installation on the border between LPZ0 and LPZ1 zones or higher.


SUG-RS232-2P diagram

Simplified internal schematic.


To ensure proper surge protection, it is recommended to use limiters at both ends of the transmission line and properly ground them.


RS232 COM Port Surge Protection

Proper use of the product for RS-232 port protection.


Short technical specification

Number of protected channels
Input / output connector
Rated DC voltage (Un)
Maximum DC voltage (Uc)
Maximum AC voltage (Uc) 12V
Rated current (In)
C1: Discharge current line-line 8/20µs (In)
C2: Discharge current line-ground 8/20µs (In) 10kA
C2: Maximum discharge current line-ground 8/20µs (Imax) 20kA
D1: Maximum lightning current 10/350µs (Iimp)
Protection level 1kV/μs (line-line) Up 20V DC
Series resistance
7Ω / line
Dimensions 57 x 32 x 28 (mm)
Mounting method Freestanding housing
Grounding method
Housing tightness IP20
Operating temperature -40ºC~80ºC