Basler Electric SR4A1B05A3A – Static Voltage Regulator for 480 V Systems

The Basler Electric SR4A1B05A3A is a compact static voltage regulator intended for synchronous generators with nominal sensing voltage of 480 V AC. It delivers a regulated DC field output of 62.5 V at 10 VA, providing stable excitation for small to medium‑sized alternators in industrial, agricultural, and standby power applications.

Regulation and Control

This regulator uses a PWM power stage for high efficiency and low heat generation. It continuously monitors the generator terminal voltage and compares it to an adjustable reference, modulating the field current to maintain the setpoint within ±0.5% accuracy. The SR4A1B05A3A includes adjustable stability (gain) and under‑frequency roll‑off to protect the generator during speed variations. A soft‑start function gradually applies excitation to reduce mechanical stress on the prime mover.

• Sensing input: 480 V AC ±10%, 50/60 Hz

• Field output: 62.5 V DC, continuous current 0.16 A (10 VA)

• Regulation accuracy: ±0.5% of setpoint

• Voltage adjustment range: ±10% of nominal

• Stability adjustment: continuous trimpot

• Under‑frequency roll‑off: adjustable 45–60 Hz

• Protections: over‑excitation limiting, loss of sensing

• LED indicators: power and regulation status

• Mounting: panel or chassis, with integral heat sink

• Operating temperature: –20 °C to +60 °C

Typical Applications

This regulator is commonly used on generator sets rated up to 200 kVA, in applications such as backup power, marine auxiliary, and remote sites. Its 480 V sensing capability makes it suitable for industrial plants with medium‑voltage distribution.

Installation and Tuning

Mounting is straightforward with four screws, and all connections are made via pluggable terminal blocks. Two trimpots—voltage and stability—allow quick field tuning. Diagnostics LED assist in verifying correct operation during commissioning.

Durability and Compliance

Constructed with industrial‑grade components and conformal coating, the SR4A1B05A3A resists moisture and vibration. It complies with CE and RoHS standards, ensuring safe and reliable operation.

In summary, the Basler Electric SR4A1B05A3A provides precise, cost‑effective voltage regulation for generators in 480 V systems, with robust performance and easy configuration.