SX440 Automatic Voltage Regulator

Description:

The SX440 Automatic Voltage Regulator (AVR) is used in brushless generator systems to automatically regulate alternator output voltage by controlling the exciter field current. Commonly installed in diesel and gas generator sets to maintain stable output voltage during changing load conditions and engine speeds. Maintenance teams and generator technicians use the SX440 AVR for generator repairs, preventive maintenance, and replacement of failed voltage regulators to ensure reliable power generation and protection of connected equipment.

Applications:

The SX440 Automatic Voltage Regulator is widely used in industrial and commercial generator systems requiring precise voltage regulation. It is commonly found in standby generators, prime power generators, marine generators, and mobile power units where maintaining stable AC output is critical for powering sensitive electrical equipment. The SX440 is compatible with many Stamford-style brushless alternators and aftermarket generator systems.

Technical Specifications:

• Manufacturer: Stamford / Compatible Aftermarket Manufacturers
• Part Number: SX440
• Product Type: Automatic Voltage Regulator (AVR)
• Input Voltage: 190–270 VAC
• Output Voltage: Max 95 VDC
• Frequency: 50/60 Hz
• Excitation Type: Self-Excited / Shunt Excitation
• Voltage Regulation Accuracy: ±1.0%
• Excitation Current: 4 A Continuous, 6 A Intermittent for 10 Seconds
• Voltage Build-Up: Residual Voltage Above 4 VAC at AVR Terminals
• External Voltage Adjustment: ±10% with 1 kΩ Potentiometer
• Under speed Protection: Adjustable Frequency Roll-Off
• Soft Start Ramp: Built In
• Sensing Input: Single Phase, 190–270 VAC
• Mounting Type: Panel Mounted
• Operating Temperature: -40°C to +70°C
• Compatible Equipment: Stamford Alternators and Compatible Brushless Generators
• Application: Diesel and Gas Generator Voltage Regulation
• Features: Automatic Voltage Regulation, Overexcitation Protection, Adjustable Stability, EMI Suppression
• Status: Active Replacement Component Available Through OEM and Aftermarket Suppliers

Common Replacements:

• Stamford SX440
• Stamford MX341
• Stamford AS440