Variable Transformers

Alliance Engineering Company

Alliance Engineering Variable Transformers (also known as Dimmerstats or Variacs) are continuously variable autotransformers designed for smooth, stepless control of AC output voltage from 0V to 270V (single phase) or 0–470V (three phase). Available in a wide range of current ratings from 2A to custom high-current configurations, and in both single-phase and three-phase versions. Supplied as standalone bench-mount tabletop units or integrated panel-mount assemblies with analog voltmeter, ammeter, MCB protection, and pilot indication. Widely used in laboratories, test benches, production lines, and industrial process control wherever precise voltage variation is required. Manufactured under ISO 9001:2015 standards by Alliance Engineering Company.

Key Technical Advantages

Output Voltage

0 – 270V (1-Ph) / 0 – 470V (3-Ph)

Current Rating

Multiple / Custom

Phase Configuration

Single Phase / Three Phase

Control

Continuously Variable Rotary Dial

Mounting

Bench Mount / Panel Mount

Certification

ISO 9001:2015

Technical Specifications

Validated industrial performance metrics for enterprise deployment.

Engineering Data Sheet IS 5142

Parameter	Specification
Standard	IS 5142
Type	Variable Autotransformer (Dimmerstat / Variac)
Phase Configuration	Single Phase / Three Phase
Input Voltage	230V AC (1-Ph) / 415V AC (3-Ph), ±10%
Input Frequency	50Hz
Output Voltage Range	0 – 270V AC (1-Ph) / 0 – 470V AC (3-Ph)
Current Rating	2A / 5A / 10A / 15A / 20A / Custom
Voltage Control	Continuously variable rotary dial with graduated scale
Waveform	Sine wave (no distortion)
Voltage Regulation	≤ 1% (no load to full load)
Efficiency	≥ 95%
Insulation Class	Class F (155°C)
Insulation Voltage	2kV (rms) for 1 minute
Core Material	CRGO Steel (toroidal)
Winding Material	Copper
Brush Contact	Carbon brush on toroidal winding
Protection (Panel Variant)	MCB overload protection + Pilot lamp
Indication (Panel Variant)	Analog Voltmeter + Pilot Lamp
Enclosure	MS Powder Coated Cabinet (bench) / Open Frame (panel)
Mounting	Bench Mount / Tabletop / Panel Mount
Operating Temperature	-10°C to +50°C
Humidity	Up to 95% RH non-condensing
Temperature Rise	≤ 50°C above ambient at full load

Standards & Compliance

Certified engineering excellence across regional and global regulatory frameworks.

IS 5142

Compliance with standard engineering and safety performance metrics.

IEC 61558-2-14

Compliance with standard engineering and safety performance metrics.

ISO 9001:2015

Certified Quality Management Systems for precision manufacturing.

Precision Configurations

Industrial Customizations

Our modular engineering workflow allows for specific adaptations to meet your site-specific infrastructure requirements. Consult with our technical team for bespoke builds.