Basler Electric 9105100106 UFOV‑250A Underfrequency/Overvoltage Protector

The Basler Electric 9105100106, known as the UFOV‑250A, is a solid‑state protection device that combines underfrequency and overvoltage sensing in a single compact unit. It is designed to protect generators, transformers, and industrial loads from abnormal frequency and voltage conditions that can cause equipment damage or system instability. The device provides two independent adjustable setpoints for frequency and voltage, each with dedicated output relays.

The UFOV‑250A uses precision measurement circuits to monitor the AC waveform and triggers a trip signal when the frequency drops below or rises above the programmed thresholds, or when the voltage exceeds the overvoltage setting. Its fast response ensures rapid fault clearing, enhancing overall system reliability.

Key Features

• Dual protection: underfrequency and overvoltage

• Adjustable frequency range: 45–65 Hz

• Adjustable voltage range: 80–140% of nominal

• Independent trip and alarm outputs

• Digital display for setpoint and measured values

• Reset and inhibit inputs for remote control

Technical Specifications

Input voltage: 120/240 VAC, 50/60 Hz; accuracy: ±0.1 Hz, ±1% voltage; response time: < 100 ms; output relays: 2 x SPDT, 5 A rating; operating temperature: -20°C to +60°C; enclosure: IP40.

Applications

Commonly installed in standby generator sets, co‑generation plants, and utility interface panels. The UFOV‑250A prevents generator overspeeding due to loss of load, protects motors from low‑frequency damage, and safeguards sensitive electronics from overvoltage surges.

Installation and Configuration

Mount the unit on a panel using the provided brackets. Connect the AC sensing leads to the monitored bus, and wire the output relays to the trip circuit. Configure the frequency and voltage setpoints via the front‑panel potentiometers and DIP switches. An optional remote reset input allows external control of the reset function.

Reliability and Self‑Diagnostics

The UFOV‑250A incorporates self‑monitoring features, including loss‑of‑sensing detection and internal fault indication. Its rugged construction and conformal‑coated PCB protect against moisture and dust. Periodic calibration checks are recommended to maintain accuracy.

Why Choose the UFOV‑250A?

This protector offers a simple yet effective solution for dual‑parameter protection. Its proven analog design ensures high immunity to noise and transient disturbances, making it suitable for harsh electrical environments. Basler Electric’s reputation for quality guarantees reliable protection for your critical assets.

In summary, the Basler Electric 9105100106 UFOV‑250A is an essential device for maintaining power system integrity by swiftly responding to frequency and voltage anomalies.