Precautions for Installing Low-Level Vibrating Rod Level Switches

Jiwei Vibrating Rod Level Switch adopts a unique double-rods design, the main applications are for granular, powdery and fine-grained bulk solids level measurements. By adjusting the resonant frequency of the inner and outer vibration rods to be completely consistent, the instrument has great reliability and detection sensitivity. Innovative developed technology enables the sensor to detect fine-grained solids with density as low as 0.02 g/cm³. Vibrating Rod Level Switches are usually installed in storage tanks, silos or containers for both high level alarm overflow detection and low level alarm dry-run protection. During installation, side-mount or top-mount is depending on the application conditions.

Improper installation may induce the risk of instrument damage and false operation. Especially when the particle sizes are different and with rough, abrasive surface, if the instrument is at low-level position, following risks may occur:

Vibrating Rod Level Switch

1. For lopsided material accumulation, the probe is easy to distort or damage due to the lateral extrusion force when it is covered by the medium;

2. When the silo is in the process of discharging, the probe is frequently collided, rubbed and squeezed by lumpy medium;

3. For slightly boiling medium, the falling and smashing of medium after purging also increases the risk of extrusion and distortion of the probe.

To prevent the above risks, Vibrating Rod Level Switch should be mounted far away from the filling point and the accumulation point when in low-level alarm applications, and the insertion depth is recommended to be as short as possible to avoid frequent extrusion, wear and deformation of the probe.

Top-mounted and side-mounted Vibrating Rod Level Switches

In order to ensure the endurance of the instrument and reliable measurement, we suggest installing a strong stainless-steel or iron protective baffle above the instrument probe to protect the probe from direct impact damage of falling materials, and also prevent generating false signals.

The shape of the protective baffle includes convex shape (inverted “V” section), concave shape (erected “v” section), arc shape, flat plate, etc. In practical applications, convex shape and concave shape protective baffles have better protection effects.

Convex shape (inverted “V” section) and concave shape (erected “v” section) protective baffle

Concave shape: It is mainly applicable to the coarse, lumpy and abrasive medium (such as small gravel, glass slag and metallic slag). This baffle allows materials to form a certain accumulation in the concave groove. The mutual impact and wear between materials in the concave groove can reduce the direct impact on the baffle and to enhance its endurance.

Convex shape: Materials slide along both sides of the baffle when falling. Because the baffle is directly impacted by materials, so only suitable for measuring fine-grained granules or powdery materials with low density and smooth surface. It is especially suitable for food industry (such as wheat, rice and flour) that the silo is required to be emptied in time and cleaned regularly.

When selecting the process connection, if possible, it is recommended to select a large flange connection, so the baffle can directly weld onto the flange.