Time Mark Corporation A258B-480VAC-3PH Power Monitor

Description:

The Time Mark Corporation A258B-480VAC 3-Phase Power Monitor is designed to continuously monitor 480 VAC three-phase power systems for phase loss, phase reversal, and undervoltage conditions, protecting motors and industrial equipment from abnormal power conditions. Commonly installed in motor control centers, HVAC systems, compressors, pumps, conveyors, and manufacturing equipment where reliable three-phase power monitoring is critical. Maintenance teams, OEMs, and system integrators use the A258B-480VAC for replacement, repair, retrofit, and preventive maintenance to improve equipment reliability and reduce costly downtime.

Applications:

The Time Mark A258B-480VAC is a solid-state three-phase monitoring relay that continuously supervises Wye or Delta power systems without requiring a neutral connection and automatically de-energizes its output relay whenever phase loss, phase reversal, or undervoltage conditions are detected. It is widely used in industrial automation systems, motor control panels, water and wastewater facilities, HVAC equipment, compressors, conveyors, and process machinery where dependable three-phase power monitoring helps prevent motor damage and production interruptions.

Technical Specifications:

• Manufacturer: Time Mark Corporation
• Manufacturer Part Number (MPN): A258B-480VAC
• Product Type: 3-Phase Power Monitor Relay
• Series: 258 Series
• Nominal Voltage: 480 VAC (Phase-to-Phase)
• Voltage Adjustment Range: 380–480 VAC
• Frequency: 60 Hz (400 Hz model available)
• Monitoring Functions: Phase Loss, Phase Reversal, Undervoltage Protection
• Output Contacts: SPDT, 10 A at 240 VAC Resistive
• Power Consumption: 3.7 W
• Response Time: 50 ms
• Reset: Automatic
• Mounting: 8-Pin Plug-In Socket
• Visual Indicators: TRIP and NORM LEDs
• Wye/Delta Compatible: Yes (No Neutral Required)
• Certifications: UL Recognized, CSA Certified
• Operating Temperature: -40°F to +131°F (-40°C to +55°C)
• Application: Three-phase motor protection, industrial automation, HVAC systems, pumps, compressors, conveyors, and process equipment.

Common Replacements:

• Time Mark A258BM-480VAC
• Time Mark B258B-480VAC
• Time Mark A263