Surge Arresters

Surge Arresters

Surge arresters are protective devices designed to preserve availability and prevent damage to sensitive electronics in instrumentation and control systems. Endress+Hauser emphasizes that short production failures can be costly and that direct/indirect lightning and switching operations can introduce voltage overloads into supply lines and communication circuits, including fieldbus systems - making deliberate surge protection a core reliability measure.

The category covers protection at multiple installation points and circuit types. Endress+Hauser lists surge arresters for DIN-rail mounting, field mounting, signal cables, fieldbus communication lines, and power lines, with primary use across process automation and measurement/communication technology in sectors such as chemicals, pharmaceuticals, water/wastewater, and food. Functionally, these devices route overvoltage surges from 4…20 mA signal cables, fieldbus lines (HART, PA, FF), and power lines safely to ground, while avoiding interference voltage drops through impedance-free connection concepts.

Beyond basic protection, model options can align with safety and hazardous-area requirements. Endress+Hauser notes optional ATEX and SIL2 intrinsically safe approvals (depending on product), availability for both field and DIN rail mounting, and increased plant availability when protection is matched to the electronics commonly used in process automation and measuring technology.

Typical applications include protecting outdoor instruments on long cable runs, safeguarding control-cabinet I/O and marshalling in lightning-prone regions, and hardening fieldbus trunks and spurs where surge energy can propagate widely. They are also relevant when adding remote skids or extending networks into exposed areas, where cable routing and grounding conditions may differ from the core facility.

Engineering considerations include coordination with the site grounding and bonding strategy, placement relative to lightning protection zones, and ensuring compatibility with signal levels and communication requirements. Proper installation (short ground paths, correct bonding, and appropriate mounting location) is as important as device selection, and periodic inspection/testing practices help ensure protection remains effective after transient events.

At Eastern Controls, We are proud to be the exclusive authorized sales and service representative for Endress+Hauser.