Description

PR3-E-180kW 250A Three-Phase Burst Fire Power Controller

The PR3-E-180kW from United Automation is a heavy-duty three-phase thyristor stack designed for precise control of large resistive heating loads using advanced two-thirds burst-fire control.

Engineered for demanding industrial heating environments, this controller uses fast pulse zero-voltage switching to minimise flicker and eliminate RFI, while offering flexible control options, intelligent fault detection, and integrated thermal protection.

Key Features

• High power capability: 180kW (250A) at 415V RMS
• Two-thirds burst-fire control for efficient three-phase load management
• Fast pulse zero-voltage switching to reduce flicker and RFI
• DC signal control and manual control options
• Automatic reset thermal trip for safe operation
• Phase loss and sensor loss detection with LED diagnostics
• Voltage-free alarm relay with selectable fault logic
• Identical physical size to 150kW model for simplified panel design
• Integrated cooling fan as standard (230V AC)

Technical Specifications

• Power rating: 180kW (250A) at typical 415V RMS supply
• Input voltage: 400V RMS ±10%
• Frequency: 50/60Hz

Control input options

• 0–10V DC (standard) or 0–5V DC via SW3
• Manual control using 5kΩ potentiometer
• 4–20mA input: set SW-I/V to ON, fit 270Ω across SIG+/-, set SW3 to 0–5V

Burst fire modes

• Slow burst: 1-second proportional time base
• Fast burst: variable, non-proportional time base

Alarm relay

• Voltage-free contact rated 125V AC at 2A
• Selectable logic via SW1:
  • OFF: relay energised (NC), trips on fault
  • ON: relay de-energised (NO), closes on fault

Status indication

• LED intensity tracks control signal
• Distinct flash codes for over-temperature, phase loss, and sensor loss

Cooling

• 120mm fan, 230V AC fitted as standard (110V and 24V options available)

Thermal protection

• Trip at 90°C ±1°C
• Reset at 85°C ±1°C

Connections

• Phase power: M8 stud terminal
• Earth: M6 stud terminal
• Control and alarm: 2.5mm² rising clamp terminals

Terminal torque

• M8: 12–15Nm
• M6: 4.5–5.5Nm

Fusing

• 315EET (315A) high-speed semiconductor fuse for 180kW model

Environmental

• Maximum working temperature: 65°C

Dimensions and weight

• 266mm (D) × 345mm (W) × 250mm (H)
• Fixing centres: 322mm × 160mm (4 × 5mm holes)
• Weight: approximately 15kg

Applications

Designed for large industrial resistive heating systems:

• HVAC heating systems
• Industrial furnaces
• Ovens
• Dryers
• Process heating equipment

Safety Notes

• Isolate supply before removing the cover
• Heatsink and internal metal parts may become very hot during operation
• Do not obstruct enclosure ventilation slots