Basler PRS 250 Veri‑Sync Relay

The Basler PRS 250 is a solid‑state synchronizing relay engineered for automatic paralleling of generators with a live bus. It monitors voltage, frequency, and phase angle between an incoming generator and the bus, issuing a close command only when all conditions are within preset limits. This ensures smooth, shock‑free connection and protects both the generator and the system from damaging transients.

Key Features

The PRS 250 offers independent adjustable setpoints for voltage difference, frequency slip, and phase angle. High‑accuracy measurement circuits provide reliable operation even in noisy electrical environments. The relay includes a built‑in time delay and a solid‑state output contact capable of direct breaker control. Front‑panel LEDs indicate power, ready, and close status.

Technical Specifications

Input voltage: 80‑240 VAC, 45‑65 Hz. Voltage matching accuracy: ±0.5%. Frequency difference: 0.05‑0.5 Hz (adjustable). Phase angle compensation: 0‑30 degrees. Output contact rating: 5 A at 250 VAC resistive. Operating temperature: -20°C to +70°C.

Operating Principles

The relay continuously compares the incoming generator voltage and frequency with the bus reference. When the differential values fall within the set window, the phase‑angle detector monitors slip frequency. Upon detecting zero phase angle crossing, the relay energizes the close output. Supervision circuits ensure the close command is issued only once per event.

Applications

Typical applications include paralleling diesel or gas generators to a utility grid, emergency standby systems, and marine power management. It is also used in peak‑shaving plants and renewable energy integration.

Installation and Configuration

Mount via DIN rail or surface screws. Connect voltage inputs, output contacts, and auxiliary power. Configure using onboard potentiometers and DIP switches. Periodic verification of setpoints is recommended.

Maintenance and Reliability

With no moving parts, the PRS 250 offers high reliability. Routine inspection of connections is sufficient.

Conclusion

The Basler PRS 250 Veri‑Sync relay delivers dependable synchronization with flexible adjustments, essential for any generator paralleling system.