Microwave Barrier Level Measurement

Microwave Barrier Level Measurement

Microwave barrier instruments provide contact-free point level detection for bulk solids using a transmitter/receiver arrangement. They are frequently selected where intrusive probes are limited by buildup, mechanical loading, or risk of jamming, and where reliable “present/not present” detection is needed for protection, counting, or positioning tasks. The approach is also used in challenging mechanical layouts such as chutes, shafts, and free-fall sections where conventional switches are difficult to mount or maintain.

The measuring principle is based on microwaves operating in a transmitter/receiver configuration. Devices detect bulk solids using this interaction, and movement or presence can be evaluated using Doppler-based effects, converting the microwave signal behavior into a discrete switching output. Installation can be executed in containers, conduits, shafts, or free-fall shafts, and measurement can be performed through non-metallic container materials from the outside in appropriate designs.

Benefits are strongly linked to non-invasive implementation. Microwave barriers can be mounted externally in certain cases, avoiding penetrations and reducing exposure of hardware to abrasive solids. They are described as largely unaffected by process conditions, mechanically robust, and essentially maintenance-free, providing a durable solution where wear-and-tear is a dominant failure driver. They also help avoid jamming and support non-contact counting/positioning functions in bulk handling systems.

Typical applications span a broad set of bulk products and packaging scenarios. Examples include wood chips, paper and carton chips, lime, pebbles, sand, as well as detection of bags and complete boxes. Use cases include chute blockage detection, conveyor transfer monitoring, hopper feed verification, and presence detection in pneumatic or gravity-fed transport paths. These devices are often deployed where rapid, repeatable switching is needed without mechanical contact.

Implementation considerations include ensuring a suitable microwave path, managing interference from nearby metal structures, and maintaining alignment between transmitter and receiver. Wall material constraints apply when “through-wall” mounting is used, and environmental approvals may be required for dusty or hazardous areas. When aligned with the mechanical design of the handling system, microwave barriers provide a reliable, low-maintenance switching layer for bulk solids control and protection.

Instrumentation and Controls., an exclusive authorized representative of sales and service for Endress+Hauser.