HollySys ALZK500 Rotary Paddle Level Switch Liquid Level Sensing

The ALZK-500 rotary paddle level switch provides reliable solid-state material detection for powder and granular applications. Engineered for robust performance, this unit integrates seamlessly into industrial control architectures.

The ALZK-500 rotary paddle level switch is a specialized field control device engineered to detect the level height of solid materials such as powders and granular substances in industrial processing environments. Plant operators and maintenance engineers in sectors like food processing, pharmaceuticals, and chemical manufacturing face persistent challenges regarding reliable solid detection under harsh dusty conditions, material caking, and mechanical wear. This product solves these issues by employing a specialized sealing design, exceptional overload protection capabilities, and a simplified mechanical installation framework. Operating primarily within the field control layer of industrial automation architecture, it interfaces directly with local relay logic or programmable logic controllers to prevent bin overflow, run-dry conditions, and material starvation. By converting mechanical paddle resistance into reliable electrical switching signals, it ensures continuous, automated inventory monitoring without requiring complex calibration routines.

Technical Specifications

Measurement Range: 0 ~ 2000 mm

Operating Temperature: -10 ~ 350 ℃

Power Supply: 24 VDC / 220 VAC

Housing Material: Die-cast aluminum alloy

Enclosure Protection: IP65

Process Connection: G1 thread flange

Torque Range: Adjustable multi-stage tension

Output Contact: SPDT relay output 5 A @ 250 VAC

How It Works

The operational cycle relies on a synchronous micro-motor driving a rotational paddle at a constant, low velocity when the measuring chamber is free of material.

As bulk solids accumulate and submerge the paddle blades, the physical resistance halts the rotation of the internal shaft, generating a reactive torque against the internal spring mechanism.

This rotational deflection forces a micro-switch actuator to trigger, altering the electrical contact state to signal a high-level alarm or control interlock condition.

Once the material level recedes below the paddle radius, the internal spring tension restores the primary shaft to its original position, releasing the micro-switch and resuming motor rotation.

Users can adjust the internal tension setting to match specific material bulk densities, ensuring sensitivity balance for light powders versus heavy granules.

[DIAGRAM: Exploded view of the ALZK-500 internal motor, spring tension adjustment assembly, and paddle shaft sealing arrangement]

Why This Product

When your bulk handling facility requires reliable level detection in dense, abrasive media, this product delivers exceptional durability through a reinforced shaft and bearing structure that withstands heavy side-loads.

When your application demands resistance to extreme thermal processes, this unit delivers operational stability up to 350 ℃ through specialized high-temperature isolation design.

When your installation engineers need fast, hassle-free mechanical setup, this switch provides standardized threaded flange mountings that integrate directly into existing vessel ports.

When your plant requires multi-voltage compatibility for diverse electrical panels, this equipment accommodates both 24 VDC and 220 VAC supply standards effortlessly.

When your maintenance schedule requires minimizing unexpected downtime, the robust overload protection clutch prevents motor burnouts during severe mechanical blockages.

When your procurement team evaluates long-term lifecycle value, this switch ensures dependable, low-maintenance service life backed by Beijing Zhongping Technology, providing professional technical assistance and dependable local component availability.

System Integration and Hardware Setup

Integration into industrial control cabinets or field junction boxes requires careful attention to electrical wiring practices to prevent common industrial failure modes. Connect the power supply and relay output terminals using shielded multi-core cables to isolate control signals from high-voltage motor lines and variable frequency drives. Ensure the cable shields are properly terminated at the control panel ground bus to eliminate electromagnetic interference and ground loops. When mounting the unit onto storage silos or process vessels, verify that the insertion angle avoids direct, high-velocity material impact during pneumatic filling cycles. Use appropriate thread sealants or gaskets matching the process vessel pressure rating to maintain structural integrity and prevent dust ingress at the mounting flange interface.

Reliability and Environmental Durability

Designed for demanding industrial service, the unit features an IP65 ingress protection rating that shields internal electromechanical components from fine dust accumulation and washdown sprays. The internal drive mechanism incorporates specialized thermal barriers and high-temperature lubricants to maintain operational integrity in harsh thermal environments up to 350 ℃. To maximize operational longevity, routine maintenance should include inspecting the external paddle shaft for material buildup or abrasive wear during scheduled plant shutdowns. The robust mechanical construction and rigorous factory quality control standards ensure an extended mean time between failures, minimizing unexpected operational stoppages in critical material handling lines.

Selection Guidance and Alternative Options

Selecting the correct level switch requires evaluating vessel temperature, material density, and flange connection compatibility to match process constraints accurately. For standard ambient temperature applications involving light powders, standard configurations provide optimal sensitivity and cost-effectiveness. When handling high-temperature aggregate bins or sticky chemical granules, specialized high-temperature variants or extended shaft configurations are recommended. Beijing Zhongping Technology maintains a comprehensive inventory of original industrial automation components and offers professional cross-reference selection support, ensuring fast delivery and seamless replacement for your specific plant requirements.

Frequently Asked Questions (FAQ)

1. What is the current local stock availability and delivery lead time for the ALZK-500?

Beijing Zhongping Technology maintains active regional inventory of this unit to support immediate dispatch and minimize operational downtime caused by equipment failures.

2. What warranty coverage and RMA procedures apply to this unit?

This product is supported by a comprehensive 12-month factory warranty, with localized technical support and efficient return merchandise authorization processing managed by Beijing Zhongping Technology.

3. What are the electrical power supply requirements and power consumption specifications?

The unit supports dual power input options of 24 VDC or 220 VAC, with an internal power consumption rating of less than 5 W during normal motor rotation.

4. What type of electrical output signal does the switch provide to the control system?

It provides a standard single-pole double-throw relay output contact rated for switching up to 5 A at 250 VAC.

5. What is the maximum temperature rating for high-temperature applications?

The unit is engineered to operate continuously in ambient process temperatures up to 350 ℃.

6. What mechanical thread or flange size is used for process mounting?

It utilizes a standard G1 threaded flange connection for secure vessel attachment.

7. How is the paddle sensitivity adjusted for different material densities?

Sensitivity is adjusted via an internal spring tension mechanism that allows operators to calibrate the torque threshold based on powder or granule weight.

8. What is the ingress protection rating of the enclosure against dust and moisture?

The housing is rated to IP65 standards, providing reliable protection against dust ingress and low-pressure water jets.