Description
EVR-4kW PA Phase-Angle Fan Speed Controller
The EVR-4kW PA from United Automation is a compact phase-angle power controller designed for smooth, proportional control of single-phase 230V loads. Housed in a robust metal enclosure, this unit is widely used as a fan speed controller for HVAC and ventilation systems, while also supporting precise control of heaters and other process loads.
Part of the EVR “Mini Stack” series, it integrates a high-speed semiconductor fuse, convection-cooled heatsink, adjustable soft-start, and multiple control signal options for reliable operation in demanding industrial environments.
Key Features
- Phase-angle control for smooth proportional voltage and current regulation
- Designed for fan speed control, HVAC, and motor-driven applications
- Wide control signal compatibility: manual, voltage, or current input
- Adjustable soft-start (0–20 seconds) to protect loads and extend lifespan
- Integrated SCR-type high-speed semiconductor fuse (Triac protection)
- Convection air-cooled heatsink for silent, reliable cooling
- Compact, enclosed metal design for easy installation
- Full isolation and overvoltage protection
- Available in enclosure, DIN-rail, or back-plate formats across the EVR range
Technical Specifications (EVR-4kW)
- Current rating: 17A
- Mains voltage: 230V AC +10% / −6%
- Control signal span (min): 0–5V DC
- Control signal span (max): 0–25V DC
- Control signal zero offset: 0–30% of span
- Signal input resistance: 5kΩ ±20%
- Manual potentiometer options: 2kΩ, 5kΩ, or 10kΩ
- Soft-start time constant: 0–20 seconds adjustable
- Isolation voltage: 2500V RMS
- Auxiliary control output: 5V DC
- Triac limiting RMS current: 26A
- Peak single-cycle surge current: 250A
- Maximum peak voltage: 600V
- Maximum working temperature: up to 65°C
Fuse (EVR-4kW)
- 20A, 660–690V AC, 10×38mm
- GRB / Protistor high-speed semiconductor fuse (gR curve)
Storage temperature
- 0°C to +85°C
Mechanical Details (Metal Enclosure Version)
- SKU: A72260 (Fan Speed Controller)
- Dimensions (D × W × H): 150 × 90 × 90 mm
- Fixing centres: 135mm (D) × 108mm (W)
- 4 × 5mm mounting holes
Applications
Suitable for proportional power control in:
- Ventilation and HVAC fan systems
- Motor-driven fans and air handling units
- Industrial and process heaters
- Ovens, dryers, and furnaces
- Air curtains and hot plates
- Electroplating and chemical process control
- Transformer regulation and controlled rectifiers
The EVR-4kW PA is especially effective as a simple, energy-efficient fan speed controller for mains-driven motors requiring reliable and adjustable airflow control.









