The HS-420d is a rugged, flameproof (Ex d) industrial accelerometer from Hansford Sensors, providing a 4-20mA velocity output for PLC/DCS integration, simplifying installation by eliminating safety barriers, featuring robust IP68 sealing, and designed for harsh environments like mining and general process industries for monitoring machinery like pumps, fans, and motors. 
Key Specifications

• Output: 4-20mA DC proportional to velocity.
• Certification: Flameproof (Ex d), suitable for hazardous areas (ATEX certified).
• Housing: IP68 sealed, Stainless Steel (standard).
• Mounting: Various threads (e.g., M6, 1/4"-28UNF) and options available.
• Power: 15-30V DC.
• Isolation: 500V case isolation.
• Frequency Response: Typically 10Hz to 1kHz (±5%).
• Shock Limit: Up to 5000g.
• Applications: Fans, pumps, compressors, gearboxes, conveyors, process equipment. 

Features

• No Barrier Required: Direct connection to PLCs/DCS.
• Compact: Small and lightweight for tight spaces.
• Customizable: Options for cable, connector, and sensitivity. 

Variants

• HS-420d: With Ex d terminal head.
• HS-420I: Intrinsically Safe (Ex ia) with Zener barrier requirements.