Overview
The Allen-Bradley 810-A03A is a time-delay electromagnetic relay from the proven Bulletin 810 family. This inverse time relay delivers reliable overload protection in AC and DC circuits, with a 4-amp maximum continuous current rating and 600-volt maximum voltage specification. Designed for control circuits requiring time-delayed response, the 810-A03A provides dependable performance in legacy industrial control systems and modernization projects where backward compatibility is essential.
Key Features
- Magnetically operated with inverse time-delay characteristic for smooth ramp-up protection
- Rated for both AC and DC applications in the same unit
- Maximum continuous current: 4 amps at 600VAC/DC
- Normally closed (NC) contact configuration with automatic reset option
- Open construction allows field repair and inspection
- Compact form factor for OEM panel integration
Technical Specifications
The 810-A03A meets industrial standards for overload relay performance with the following characteristics:
- Maximum Voltage: 600VAC/DC
- Maximum Current: 4 amp continuous
- Contact Type: Normally closed (NC)
- Reset Type: Automatic
- Time Delay: Inverse (current-dependent)
- Application: AC and DC circuits
- Control Circuit Rating: 120–600VAC (typical for series)
- Make Power: Approx. 7200 VA (series reference)
- Break Power: Approx. 720 VA (series reference)
Typical Applications
The 810-A03A inverse time relay is commonly used in:
- Motor starter and contactor control circuits
- Pump and compressor overload protection
- Legacy automation control panels and retrofit projects
- Machine tool electrical systems requiring time-delay response
- Industrial HVAC and process control systems
Compatibility & Replacements
The 810-A03A is part of the Allen-Bradley Bulletin 810 relay family. Modern alternatives include solid-state overload relays and digital time-delay modules; however, for systems designed around Bulletin 810 architecture, this relay remains the preferred replacement. Common related models in the 810 series include 810-A02A (3-amp), 810-A04A (6-amp), and 810-A06A (10-amp) variants. Always verify voltage, current rating, and contact configuration when selecting a replacement to ensure compatibility with your control circuit design and safety certification requirements.
