Overview
The 6GA2-491-1A is a Siemens automatic voltage regulator for 1FC6 brushless synchronous generators. Uses thyristor shunt (subtractive) control principle for precise voltage regulation with compounding excitation system.
Key Features
- Siemens Brand — Genuine AVR
- 5A Continuous / 7A Intermittent (10s) Output
- Thyristor Shunt Control
- ±0.5% Voltage Regulation
- Suitable for 1FC6 Series
Technical Specifications
| Parameter | Value |
|---|---|
| Model | 6GA2-491-1A |
| Brand | Siemens |
| Type | Thyristor Shunt AVR (Subtractive) |
| Voltage Sensing Input | 230VAC ±10% (200-240V) or 400VAC ±10% (340-480V) |
| AVR Shunt Current | 5A DC continuous |
| Max Shunt Current | 7A DC intermittent (10s) |
| Voltage Adjustment | ±5% internal rheostat; ±5-10% external |
| Droop Adjustment | 0-0.5A AC via CT |
| Regulation Accuracy | <±0.5% (engine variation <4%) |
| Operating Temp | 0°C to +70°C |
| Storage Temp | -45°C to +85°C |
| Dimensions | 242×102×48mm |
| Weight | 690±20g |
Compatibility
Designed for Siemens 1FC6 brushless synchronous generators. Compatible with Siemens-licensed Hyundai, Uljanik, Fenxi generators.
Why Choose ZenixPower
- Siemens Genuine — Authentic Siemens quality
- 5A/7A Rating — Higher current capacity for larger 1FC6 generators
- ±0.5% Precision — Stable voltage under varying loads
- Proven Design — Decades of field reliability
Specification Comparison
Compatible Generators Siemens 1FC5/1FC6 series. **Cross-series substitution is strictly prohibited! Interfaces are not compatible!**
| Model | Generator Series | Application | Price |
| 6GA2-490-0A | 1FC5 series | Land-based power generation | $150-300 |
| 6GA2-491-1A | 1FC6 series | Marine power generation | $200-350 |
| 6GA2-492-1A | 1FC6 series | Land-based power generation | $150-300 |
Selection Advice These three models are mutually incompatible. Check the generator nameplate to confirm whether it is 1FC5 or 1FC6 before purchasing. Siemens AVRs are not interchangeable with any other brand.







