Overview
The AVC63-4A 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
- Full-Wave Power Stage — Superior transient performance vs half-wave designs
- 4A Continuous / 6A Forcing — 63VDC continuous, 90VDC for 1 minute
- Peak 134VDC/9A — 10-second emergency forcing capacity
- Better than ±1% Regulation — No-load to full-load, no derating
- Frequency Compensation — Adjustable U/F curves for 50/60Hz
- Overexcitation Shutdown — 95VDC threshold with time delay
- Build-Up from 6VAC — Works with very low residual voltage
- Compact & Potted — Harsh environment rated
Technical Specifications
| Parameter | Value |
|---|---|
| Input Power | 95-139VAC, ±10%, 50/60Hz, 450VA |
| Sensing Input | 95-139VAC ±10% or 190-277VAC ±10%, 50/60Hz |
| Output Voltage | Max 63VDC at 4A DC (252W continuous) |
| Forcing Output | 90VDC at 6A DC (540W) for 1 minute |
| Peak Forcing | 134VDC at 9A DC (1206W) for 10s |
| Regulation Accuracy | Better than ±1%, no-load to full-load |
| Excitation Type | Self-excited shunt, full-wave power stage |
| UF Compensation | Yes, frequency compensation curves |
| Overexcitation Shutdown | 95VDC ±5%, time delay curve |
| Min Field Resistance | 15 ohms |
| Max Field Resistance | 100 ohms |
| Response Time | <1.5 cycles for ±5% sensing change |
| EMI Suppression | Internal EMI filtering |
| Operating Temp | -40°C to +60°C |
| Voltage Buildup | As low as 6VAC residual |
| Dimensions | 139.5 x 124.4 x 50.0 mm |
| Weight | 283g (10 oz) |
Compatibility
Same as AVC63-4, with additional suitability for generators that frequently start large motors (pumps, air conditioners, compressors).
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 Same as AVC63-4, with additional suitability for generators that frequently start large motors (pumps, air conditioners, compressors).
Competitors AVC63-4 (standard version), EA05A (KUTAI).
| Parameter | AVC63-4A | AVC63-4 | EA05A |
| Output Current | 4A cont. | 4A cont. | 5A cont. |
| Forcing/Peak | 6A forcing 1 min + 9A peak 10s | 6A forcing 1 min | 7A intermittent 10s |
| Rectification | Full-wave power stage | Full-wave rectification | Half-wave thyristor |
| Regulation | ±1% | ±1% | ±0.5% |
| Max Field Resistance | 100Ω | 100Ω | 100Ω |
| Enclosure | Potted | Potted | Standard |
| Price | $40-60 | $35-55 | $25-38 |
Selection Advice
The AVC63-4A differs from the standard AVC63-4 by offering an additional 9A peak current capability for 10 seconds. This means that when the generator starts a motor load (which draws 5-7 times rated current at startup), the AVC63-4A can supply extra short-duration excitation current to prevent voltage sag. If the generator needs to drive pumps, air compressors, or cold storage compressors that start and stop frequently, the AVC63-4A is the appropriate choice. For standard lighting and heating loads, the AVC63-4 is fully sufficient.
