Band suppressor/choke for bus system

Band Suppressor / Choke for Bus System – Technical Overview

A band suppressor, also commonly referred to as a bus choke, line choke, or common-mode choke for fieldbus systems, is a passive inductive component designed to attenuate high-frequency electromagnetic interference (EMI) and suppress common-mode noise on industrial communication networks. These devices are typically installed in series with the bus cable, offering a defined impedance at specific frequency ranges (e.g., 1–30 MHz) to block unwanted signals while allowing the desired data transmission to pass with minimal attenuation. Key technical parameters include rated current (e.g., 0.5 A to 5 A), inductance values (e.g., 100 µH to 1 mH), DC resistance (DCR), and voltage ratings (e.g., 250 V AC/DC). They are available in compact DIN-rail mountable housings or inline modules, often with integrated ferrite cores for enhanced suppression. Common bus systems supported include PROFIBUS, DeviceNet, CANopen, Modbus RTU, and AS-Interface, ensuring signal integrity in electrically noisy industrial environments.

Applications and Sectors

These suppressors are essential in industrial automation, process control, and building management systems where fieldbus networks operate near variable frequency drives (VFDs), motor starters, welding equipment, or switching power supplies. Typical installations include control cabinets, junction boxes, and distributed I/O stations. They are also used in renewable energy systems (e.g., solar inverters), transportation (railway signaling), and oil & gas facilities to protect communication lines from conducted and radiated interference. The devices help meet EMC standards such as IEC 61000-6-2 and IEC 61000-6-4.

Subcategories and Key Articles

The category includes subcategories like bus chokes for PROFIBUS (e.g., part numbers starting with 6GK or 6ES7), DeviceNet chokes (e.g., 1794 series), and CANopen suppressors (e.g., B82793 series). Key articles often follow a coding pattern: [Bus Type]-[Current Rating]-[Inductance], such as PB-1A-100µH or DN-2A-470µH. Common codes include 6GK1900-0AB00 (PROFIBUS choke) and 1794-NC1 (DeviceNet choke). These are not accessories but standalone components for direct network integration.

Business Benefits and Support

Electric Automation Network offers express worldwide shipping and dedicated engineering support for selecting the correct band suppressor based on bus type, cable length, and noise profile. Our engineers provide personalized technical assistance, real-time pricing, and detailed datasheets for each article, ensuring optimal EMC performance and network reliability.