APL210 limit switch box – Mechanical Valve Position Indicator

Product Overview

The JSW APL210 limit switch box is a compact, weatherproof enclosure designed to provide open/close signal feedback for pneumatic actuators and quarter‑turn valves. This unit transmits remote position signals while offering continuous visual rotational monitoring. It features a rugged yet compact design, making it ideal for small ball valve assemblies and applications where installation space is limited. For more about our company, please visit our about us page.

The device incorporates a visual position indicator with 0–90° rotation, displaying closed (red) and open (yellow) positions at a glance. It meets NAMUR mounting standards and ISO 5211 bracket interfaces, ensuring direct compatibility with most quarter‑turn pneumatic actuators. The enclosure is die‑cast aluminum alloy with an IP67 protection rating, resistant to dust ingress and temporary immersion. It also offers multiple cable entry options: G1/2, NPT 1/2, or M20×1.5.

Key Technical Specifications

• Модель: APL210 mechanical limit switch box
• Enclosure Material: Die-cast aluminum alloy with polyester powder coating
• Protection Rating: IP67 (weatherproof, suitable for temporary submersion)
• Mounting Interface: NAMUR standard, bracket according to ISO 5211
• Position Indicator: 0–90° rotation (closed: red, open: yellow)
• Switches: 2× SPDT mechanical micro switches (optional: proximity sensors)
• Switch Ratings: AC: 250V/3A, 125V/5A; DC: 250V/0.2A, 125V/0.4A, 30V/4A
• Terminal Strips: 8 points (0.08–2.5mm²)
• Cable Entries: G1/2, NPT 1/2, or M20×1.5 (dual entries)
• Shaft Material: Stainless steel (NAMUR standard)
• Ambient Temperature: -20°C to +80°C

For detailed product drawings and dimensional data, please contact our technical team.

Product Features

• Compact & Rugged Design: The die-cast aluminum housing with polyester coating withstands harsh industrial environments, including washdown and outdoor installations.
• Visual Position Indication: The 0–90° rotating indicator provides clear open/closed status at a glance, reducing the need to access the valve directly.
• Quick-Set Cam Adjustment: The spring-loaded splined cam allows easy on-site setting without tools, eliminating the need for readjustment after initial setup.
• NAMUR & ISO 5211 Compliance: Directly mounts onto any NAMUR-standard pneumatic actuator, with ISO 5211 brackets for secure, bracket-free installation.
• Flexible Cable Entry Options: Dual cable entries (G1/2, NPT 1/2, M20) allow convenient wiring from either side, simplifying installation in tight spaces.
• Multiple Switch Configurations: Available with 2× SPDT mechanical switches or optional proximity sensors (PNP/NPN), supporting both basic on-off feedback and advanced control systems.
• Secure Cover Design: Captive cover bolts prevent loss during maintenance, ensuring fast and worry-free access for adjustments.
• Optional Explosion-Proof Versions: ATEX-certified models are available for explosive atmospheres (Ex d IIB T6, Ex ia IIC T6) upon request.

Working Principle

The switch box operates via a mechanical cam mechanism driven by the actuator’s rotary motion. When the pneumatic actuator rotates 90°, the stainless steel shaft transfers this motion to internal adjustable cams. These cams then actuate two independent SPDT micro switches, sending an electrical open or closed signal to the control room or PLC. Simultaneously, the visual indicator rotates between red and yellow to show the valve’s physical status.

The “quick-set” spring-loaded splined cam design allows rapid adjustment without tools, and the captive cover bolts ensure a secure, weatherproof seal. This reliable, fail‑safe design provides accurate feedback and facilitates proactive maintenance.

Applications

Thanks to its compact size and IP67 protection, the APL210 limit switch box is ideal for space‑constrained and challenging environments:

• Small Ball Valve & Butterfly Valve Assemblies: Ideal for compact pneumatic actuators where space is limited.
• Water & Wastewater Treatment Plants: Provides reliable valve position feedback in damp and corrosive environments.
• Oil & Gas Pipelines: Remote valve stations require accurate open/closed indication for safety and operational control.
• Chemical & Petrochemical Plants: Delivers essential valve status feedback for critical isolation and shut‑down valves.
• Pharmaceutical Manufacturing: Stainless steel shaft and optional clean‑room materials meet hygiene requirements.
• Food & Beverage Processing: Washdown‑resistant design suits applications requiring regular cleaning.
• Power Generation Facilities: Monitors cooling water systems, fuel handling, and steam isolation valves.

Quality Assurance

JSW produces this device under strict quality control, certified to ISO 9001:2015. Our facility also maintains ISO 14001:2015 and ISO 45001:2018 certifications. Each unit undergoes functional testing, insulation resistance testing, and IP67 verification before shipment. All components are traceable, and a certificate of conformance accompanies every order. For detailed documentation, please visit our certificates page.

Customization Options

JSW offers several customization options for this model, including alternative materials (stainless steel housing), extended temperature ranges (‑40°C to +150°C), additional cable entries, proximity sensors (PNP/NPN), ATEX explosion‑proof versions, and custom colors. For more information, please contact our engineering team.

Related Products

Beyond this unit, JSW offers a complete range of valve automation components, including pneumatic actuators, SD series manual override gear boxes, and AM series gear boxes. For a full product overview, visit our home page.