RS-485 Bus Surge Protection Mounted on DIN Rail

The SUG-RS485/DIN is designed to protect the RS-485 bus from surges caused by atmospheric discharges and potential differences.

Modern solutions in the form of MOSFET fuses limit the flow of large 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 equalizing currents, which can protect RS-485 interfaces from potential jumps that lead to overcurrent.

The structure consists of voltage clipping and limiting stages, as well as a current limiter above 300mA. The product has very low attenuation, making it possible to transmit data at very high speeds.

The built-in additional protective circuit for the wire screen can be indirectly grounded through a gas discharge tube (GDT) or directly to the ground. Connecting terminals 3 and 4 closes the connection of the wire screen to the ground.

The overvoltage protection is designed to be mounted on a DIN 35mm rail. High-quality window clamps with high current load limit the risk of damage during large shock impulses and temporary current overloads. The device occupies the width of one DIN standard module.

The product is recommended for installation at the boundary of LPZ0 and LPZ1 zones or higher.

Simplified internal diagram.

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

Proper use of the product for protecting the RS-485 bus from overvoltage.

Short technical specification