Shortcomings of Adjustable Shaft Rotary Paddle Level Switches

The adjustable design significantly reduces the reliability due to the gap of the adjustable sleeve.

The working principle of Rotary Paddle Level Switch is based on an electric motor that turns at a certain speed, through a transmission and a shaft equipped with a paddle.

Rotary Paddle Level Switches are used in silos, bins, tanks and hoppers to detect high and low levels of bulk solids. When the product level reaches the paddles, the material slows down the rotation and stops the motor, which triggers the switching signal of the sensor.

Rotary paddle technology has been used for many years, providing point level indication and bin level switching in many industries. Rotary Paddle Level Switches are widely used in silos for grain, sugar, cocoa, animal feed, powder, fine ash, lye, chalk, plaster, wood chips, etc.

It can be seen from working principle, the transmission shaft of Rotary Paddle Level Switch is always rotating when in operation, the sealing between the shaft and the outer sleeve is the main technical difficulty, as well as the sealing performance is a significant factor for the sensor’s quality and reliability. The non-adjustable Rotary Paddle Level Switch gets stuck due to poor sealing after being used for a long time, especially when measuring materials such as powder or fine ash. This is also the main reason why the service life of Rotary Paddle Level Switch is short, and requires regular maintenance.

Part of the reasons for the design of the adjustable Rotary Paddle Level Switch is because of the unknown size of the silo, or the irregularly piled up of materials. The length of the shaft can be adjusted anytime. But, in fact, this adjustable design significantly reduces the reliability due to the gap of the adjustable sleeve. The sealing problem of the adjustable sleeve degrades its protection level, and fine powder is more likely to penetrate into the sleeve, causing shaft jamming, which ultimately leads to shorter service life and less durability than non- adjustable Rotary Paddle Level Switches.

To keep the durability of the Rotary Paddle Level Switch, a high-quality motor is required, and it is particularly critical to improve the protection level and sealing performance.