Overview
The United Electric J54A 144 is a precision pressure switch designed for industrial process control and safety applications. With a 0-20PSI setpoint range, this switch delivers reliable on/off control for pump protection, alarm monitoring, and system interlocks across hydraulic, pneumatic, and fluid systems.
Key Features
- Dual SPDT outputs — Two independent snap-action switch contacts; configurable as normally open or normally closed
- Internal hex adjustment — Set pressure via 1/4″ hex wrench; no reference dial needed for field commissioning
- Brass bellows construction — Durable sensing element rated for extended cycle life
- NEMA 1 enclosure — Black Lexan® polycarbonate housing protects internal contacts; suitable for machine-mounted installations
- Compact footprint — Space-efficient design for retrofits and confined panel layouts
- Standard 1/4″ NPT female pressure connection — Direct line mounting without adapters
Technical Specifications
- Pressure range: 0–20 PSI
- Setpoint repeatability: ±1% of full scale
- Switch type: Two SPDT snap-action contacts
- Electrical rating: 15A @ 125/250/480 VAC resistive
- Enclosure material: Lexan® black finish (NEMA 1)
- Pressure connection: 1/4″ NPT female, nickel-plated brass
- Ambient temperature: 0–160°F (–18–71°C)
- Storage temperature: –65–160°F (–54–71°C)
- Weight: Approximately 12 oz
- Maximum wire size: 16 AWG (75°C rated copper)
- Shock rating: Repeats after 15 G, 10 ms duration
- Vibration rating: Repeats after 2.5 G, 5–500 CPS
Typical Applications
- Hydraulic system pressure monitoring and pump shutdown
- Pneumatic system low-pressure alarms and safety interlocks
- Compressed air line protection and regulation
- Water system pressure monitoring in HVAC and industrial plants
- Refrigeration system supervisory control
- General industrial process control requiring two independent switch outputs
Compatibility & Replacements
Compatible With
- Standard industrial control panels and relay systems
- PLC and motion control inputs (24 VDC or 480 VAC coil circuits)
- Pressure line systems using 1/4″ NPT female connections
- HVAC, refrigeration, hydraulic, and pneumatic systems
Replaces / Drop-In Replacement For
- United Electric J54-144 (single SPDT model)
- Earlier J54A versions with different pressure ranges or output configurations
- Verify pressure range and contact configuration against your existing unit before ordering
Works With
- Electrical: 480VAC / 125/250VAC three-phase and single-phase systems
- Mounting: Direct line mount via NPT; compatible with standard bracket kits (optional)
- Control interfaces: Hardwired relay logic, conventional pneumatic controls, and discrete PLC inputs
- Pneumatic/hydraulic: Any fluid system rated for brass bellows compatibility
