Product description of Leroy somer R448
Leroy-Somer R448 Automatic Voltage Regulator (AVR) is a proven digital control unit designed to stabilize output voltage in synchronous alternators used in industrial, commercial, and marine generator sets. The regulator receives its supply directly from the main windings (140 V, 50/60 Hz) through terminals X1 and X2, so it eliminates the need for an external auxiliary supply. As a result, installation becomes simpler and faster. Moreover, the AVR continuously monitors alternator voltage and instantly adjusts the excitation current to the rotor field. This action maintains steady voltage even when the generator faces sudden load changes.
Because modern loads include sensitive electronics, voltage stability matters more than ever. Therefore, the R448 reacts quickly to starting motors, switching loads, and fluctuating demand. Operators benefit from stable lighting, safe control panels, and protected automation equipment. In addition, built-in protection circuits reduce over-excitation and prevent field damage. The regulator also integrates easily with most Leroy-Somer and compatible alternators, which makes it a preferred replacement or upgrade solution in generator maintenance projects.
Advanced Control Features and Easy Adjustment
The R448 AVR combines precise sensing with practical adjustability. For instance, accessible potentiometers allow technicians to set voltage, stability, and response speed directly on site. Consequently, field tuning becomes straightforward without specialized software. The unit also supports parallel generator operation using droop current transformer compensation, so multiple alternators can share load smoothly. Furthermore, soft-start voltage build-up protects connected equipment during generator startup.
Another important advantage lies in durability. The regulator uses industrial-grade electronic components and a vibration-resistant design, ensuring reliable operation in demanding environments such as factories, construction sites, and standby power stations. In addition, frequency protection reduces excitation if engine speed drops below the safe threshold, thereby preventing overheating. Maintenance teams appreciate its clear terminal layout and compact mounting size, which shortens service time. Overall, the Leroy-Somer R448 delivers consistent generator performance, longer alternator life, and dependable voltage control in both prime and backup power applications.
Technical Specifications Leroy somer R448
| Parameter | Description |
|---|---|
| Product Type | Automatic Voltage Regulator (AVR) |
| Model | Leroy-Somer R448 |
| Supply Input | From main windings |
| Input Voltage | 140 V AC |
| Frequency | 50/60 Hz |
| Supply Terminals | X1, X2 |
| Sensing Voltage | 95–140 V AC (typical alternator sensing range) |
| Voltage Regulation Accuracy | ±0.5% |
| Build-Up Voltage | Residual magnetism assisted / soft start |
| Response Time | Fast dynamic response to load variation |
| Excitation Output | Controlled DC current to alternator field |
| Parallel Operation | Yes, with droop CT compensation |
| Under-Frequency Protection | Built-in frequency roll-off |
| Adjustment Controls | Voltage, stability, and response potentiometers |
| Operating Temperature | Approx. −20 °C to +70 °C |
| Mounting | Panel / alternator terminal box mounting |
| Application | Diesel and gas generator alternators |
Catalogue Data
| Feature | Benefit |
|---|---|
| Direct supply from main winding | No auxiliary power supply required |
| Digital voltage regulation | Stable generator output |
| Soft voltage build-up | Protects connected equipment |
| Frequency protection | Prevents overheating at low speed |
| Parallel operation capability | Suitable for multi-generator systems |
| Rugged industrial design | Long service life |
| Easy field adjustment | Quick commissioning and maintenance |
| Compatible alternators | Leroy-Somer and equivalent generators |