Run Start Capacitor, Round, 75/7.5 MFD, 440/370

Mars 12901 – Dual Run Capacitor, 75/7.5 MFD, 440/370V Round Aluminum Case

The Mars 12901 dual run capacitor is designed for high-reliability operation in HVAC applications that require simultaneous support for both a compressor and a fan motor. With capacitance values of 75/7.5 microfarads (MFD) and a voltage rating of 440/370 VAC, it serves as a direct replacement in residential and light commercial systems utilizing permanent split capacitor (PSC) motors.

This unit is constructed to meet rigorous endurance standards (EIA-456-A) and is UL-recognized for safety and performance. Its aluminum case is oil-filled and non-PCB, and includes a pressure-sensitive internal interrupter for added protection during fault conditions.

Technical Specifications

• Capacitance: 75/7.5 MFD ±6%
• Voltage Rating: 440/370 VAC, 50/60 Hz
• Case Type: Round aluminum canister
• Dielectric: Non-PCB, oil-filled
• Terminals: Standard ¼” quick-connect terminals labeled C, FAN, HERM
• Operating Temperature: -40°C to +70°C

Physical Dimensions

• Diameter: Approx. 2.5 inches
• Height: Approx. 4.9 inches (excluding terminals)

Installation Notes

The Mars 12901 should be installed by qualified HVAC technicians. Prior to replacement, verify that both capacitance and voltage ratings match the equipment’s original specification. Always discharge the capacitor before removal and confirm polarity during reconnection. Secure mounting using approved brackets or capacitor straps and ensure that all terminals are properly insulated to prevent arcing.

System Integration and Application

This dual run capacitor is suited for condenser units, heat pumps, and packaged systems where a single component supports both compressor and fan motor circuits. By combining two capacitance functions in one device, it simplifies service work, reduces space requirements, and enhances installation efficiency in tight control enclosures.

Professional-Grade Features

• ✅ Dual Value Capacitor – Supports compressor (75 MFD) and fan motor (7.5 MFD) circuits
• ✅ 440/370V Rating – Withstands higher voltage fluctuations common in residential and light commercial systems
• ✅ Pressure-Sensitive Interrupter – Provides fail-safe disconnect in overpressure or short conditions
• ✅ UL Recognized and EIA-456-A Compliant – Meets industry standards for electrical endurance and reliability
• ✅ Form-Fit Design – Compatible with OEM brackets and enclosure constraints