Variac transformer GRAY SUNTEK 1000VA 0-300V (4A)

The SUNTEK GRAY 1000 VA laboratory autotransformer is designed for continuous adjustment of AC voltage from 0 to 300 V under load, without circuit interruption, in a single-phase 220 V / 50–60 Hz network.
It is used in laboratories, on production and testing benches, and during debugging, testing, and operation of equipment with non-standard voltage requirements.

Electrical Specifications

• Rated Power: 1000 VA

• Maximum Load Current: 4 A

• Output Voltage Range: 0–300 V

• Input Voltage: 220 V, 50/60 Hz

• Warranty: 2 years

Design and Control
All controls and indicators are located on the front panel, simplifying operation and making the device ideal for integration into laboratory and production setups.
The unit is fully assembled and ready for immediate connection.

The digital display shows:

• Input voltage

• Output voltage

• Load current

• Power factor (PF)

A mechanical scale complements the voltage adjustment.
Smooth voltage adjustment is achieved via a rotary knob.
The single-use fuse is easily accessible without disassembling the device.
Load socket and euro plug are positioned on the rear panel.
The metal housing features ventilation openings for effective heat dissipation.

The device can be used both as a standalone unit and as part of larger testing systems.

Understanding Power Factor (PF)
Power factor (PF) reflects the ratio of active power to apparent power.

• PF = 1 indicates a fully efficient resistive load.

• PF < 1 is typical for inductive loads (motors, transformers), where the current is higher than calculated by P = U × I.

A low power factor increases the current in the circuit, which is why SUNTEK displays the power factor and load current separately from the voltage.

Load Calculation Example
Suppose the equipment consumes 800 W with a power factor of 0.65:

• Apparent power: S = 800 / 0.65 ≈ 1230 VA

• A 1000 VA autotransformer would be overloaded.

For stable operation, a reserve of at least 15–25% above the actual apparent power is recommended.

Operating Conditions

• Temperature: –5 °C to +40 °C

• Humidity: up to 80% at 25 °C

• Atmospheric Pressure: from 86 kPa

• Environment: non-explosive, free of conductive and abrasive dust

• Protection Class: IP20

• Continuous Operation Time: up to 6 hours

• The device must not be left running unattended.

Dimensions and Connections

• Dimensions: 230 × 200 × 170 mm

• Weight: 8.0 kg

• Connection: built-in socket and cable with euro plug

• Supplied fully assembled and ready for use

Typical Applications

• Testing and debugging of electrical devices

• Testing fuses, relays, and circuit breakers

• Working with soldering stations and temperature controllers

• Restoration of electrolytic capacitors

• Use in laboratories, technical colleges, and universities

• Industrial product development and testing

Advantages of the SUNTEK GRAY 1000 VA

• High electromechanical reliability

• Digital display of load parameters

• Convenient front panel layout for easy integration

• Engineering-focused design for practical use

• Simplified monitoring and startup

• Built for real-world laboratory and industrial applications