Voltage Regulators

AVR voltage regulators for generator sets

The automatic voltage regulator (AVR) (Automatic Voltage Regulator) is the electronic component that keeps the alternator's output voltage constant, regardless of the connected load. Without an AVR, the voltage fluctuates with every change in load, which damages the equipment connected to the generator. It is one of the most frequently replaced components in generator set maintenance and one of the first to be checked when the generator set experiences voltage problems or instability.

At Sorilux, we carry over 130 models of original AVR regulators—removed from unused alternators—as well as high-quality equivalents for the industry’s leading brands, including the range of digital excitation systems Basler DECS For industrial and high-demand applications. Express shipping (24–48 hours).

Available brands

• BASLER Electric — DECS series digital excitation control systems (DECS-100, DECS-150, DECS-250) for industrial synchronous alternators. Precise regulation of voltage, VAR, and power factor; integrated protection; and digital communication. The solution for grid-parallel installations, cogeneration, and critical applications. Original Basler Electric 100% product. Includes ICRM-7 and EDM20 add-on modules.
• Leroy Somer / Nidec — R and D series (analog and digital). Includes disassembled, unused alternator units and equivalent diode kits.
• Stamford — AS440, AS480, MX321, MX341, MX342. Includes a disassembled AS440 unit and RSK diode kits.
• Mecc Alte — DSR, SR7 2G, DER1/A, UVR6. Includes brush holders, collectors, and diodes for the T and S series.
• Marelli Motori — MARK (analog) and MEC/MGC/E-VO/D-VO (digital) series. Includes diodes, rectifiers, surge suppressors, and PT100 sensors. Most complete controllers are available upon request.
• LINZ — HVR series (HVR10, HVR11, HVR30). Includes brush holders, slip rings, and diodes for alternators in the E1S series.
• SYNCHRO — B4 and BL4 U. Includes brush holders, commutators, and a rectifier bridge.
• Sorilux — SOR series of equivalent controllers compatible with the leading brands on the market: Leroy Somer, Stamford, Mecc Alte, Marelli, LINZ, SINCRO, Basler, and Marathon.

How do I figure out which AVR I need?

The easiest way is to have the part number of the AVR currently installed on the alternator. If you don't have it, look for the alternator's nameplate: it lists the exact model, and with that information you can find the correct AVR. If you have any questions, contact us at Please provide the model number of the alternator or generator set, and we will confirm the part number before placing the order.