Overview
The R150 is an Automatic Voltage Regulator (AVR) that maintains the generator output voltage within precise limits by controlling the exciter field current. It continuously samples the generator output voltage and adjusts excitation to compensate for load changes, engine speed variations, and temperature drift.
Key Features
- 6A Continuous Output — 95VDC max, 8A intermittent for 5 seconds
- ±0.8% Regulation — Higher precision than standard R120/R180
- Wide Frequency — 20-100Hz for global compatibility
- Self-Excited Shunt — Proven reliable excitation
- Direct OEM Replacement — Drop-in for Leroy Somer R150 systems
Technical Specifications
| Parameter | Value |
|---|---|
| Sensing Input | 240VAC RMS ±20% (190-264VAC) |
| Frequency | 20-100 Hz |
| Output Voltage | Max 95VDC at 240VAC input |
| Output Current | Continuous 6A, Intermittent 8A for 5s |
| Regulation Accuracy | <±0.8% |
| Excitation Type | Self-excited shunt |
| UF Limitation | k=1.2 |
| Voltage Setting Range | ±10% |
Compatibility
Compatible with Leroy Somer LSA series alternators using SHUNT or AREP excitation. Rated for mid-size generator sets with 6A field current requirement.
Why Choose ZenixPower
- Tight Voltage Regulation — <±1% RMS regulation ensures stable generator output under 0-100% load transients
- Fast Response — Sub-0.5 second recovery time prevents voltage dips during motor starting and load switching
- Dual Excitation Compatibility — Self-excited shunt or PMG-powered configurations clearly labeled for correct selection
- Built-in Protections — Under-frequency roll-off, over-excitation limiting, and soft-start ramp as standard
- Drop-In Replacement — Terminal layout and mounting dimensions match STAMFORD, Leroy-Somer, Marathon, and Mecc Alte OEM AVRs
- Pre-Calibrated — Each AVR ships with factory-default potentiometer settings for immediate plug-and-play operation
Specification Comparison
Compatible Generators Leroy Somer LSA 42-44 series 20-200kW. Same generator family as R120, upgraded for higher power and precision.
Competitors R120 (entry), R150 (mid-range), R180 (premium solid-state). All three are direct-fit replacements within the LSA series.
| Parameter | R120 | R150 | R180 |
| Output Current | 4A cont. / 6A int. 30s | 6A cont. / 8A int. 5s | 6A cont. / 9A int. 5s |
| Regulation | ±1% | ±0.8% | ±0.5% |
| Circuit Type | Standard analog | Standard analog | Fully solid-state |
| Potentiometer Drift | Moderate (recalibrate every 2-3 years) | Moderate | None (solid-state, no mechanical pots) |
| Voltage Sensing | 190-264VAC | 190-264VAC | 190-264VAC |
| Excitation Type | Self-excited shunt | Self-excited shunt | Self-excited shunt |
| Price | $40-70 | $50-80 | $60-100 |
Selection Advice
The R150 is the best value mid-range choice in the Leroy Somer LSA series: 6A output is a 50% increase over the R120’s 4A, providing significantly more excitation headroom. At $50-80, it delivers the best price-to-performance ratio for 20-150kW generators that don’t require the ultimate in long-term stability.
The R180 is the premium choice: its fully solid-state design eliminates ALL mechanical potentiometers — the primary source of voltage drift in analog AVRs. In standard analog AVRs (R120, R150), potentiometers can drift by 1-2% per year due to vibration and temperature cycling, requiring recalibration every 2-3 years. The R180’s solid-state circuitry eliminates this entirely, making it ideal for: (1) unmanned remote sites where maintenance visits are expensive, (2) cellular tower backup generators where voltage precision is critical, (3) generators in high-vibration environments. The additional $10-20 over the R150 translates to zero recalibration costs over the AVR’s lifetime.
