Equipment - Variable Transformers

Image	Part Number	Description / PDF	Quantity	Rfq
	60M5021-4P Staco Energy Products Co.	MOTORIZED VRBLE TRANSF 280V 112A	0
	15M5021C Staco Energy Products Co.	DISCONTINUED USE MODEL 15M5021CT	0
	15M5021E-6Y Staco Energy Products Co.	MOTORIZED VRBLE TRANSF 560V 56A	0
	5M5021C Staco Energy Products Co.	DISCONTINUED USE MODEL 5M5021CT.	0
	252-3 Staco Energy Products Co.	VARIABLE TRANSFORMER 528V 0.8A	0
	15M1510C Staco Energy Products Co.	DISCONTINUED USE MODEL 15M1510CT	0
	15M5021-6D Staco Energy Products Co.	MOTORIZED VRBLE TRANSF 280V 84A	0
	30M5021E-6PS Staco Energy Products Co.	MOTORIZED VRBLE TRANSF 560V 84A	0
	60M5021-6D Staco Energy Products Co.	MOTORIZED VRBLE TRANSF 280V 84A	0
	1510C Staco Energy Products Co.	VARIABLE TRANSFORMER 140V 15A	0
	1520C-2 Staco Energy Products Co.	VARIABLE TRANSFORMER 560V 9.5A	0
	60M5021-4D Staco Energy Products Co.	MOTORIZED VRBLE TRANSF 280V 56A	0
	5021C-2P Staco Energy Products Co.	VARIABLE TRANSFORMER 280V 56A	0
	2520C Staco Energy Products Co.	VARIABLE TRANSFORMER 280V 10A	0
	15M5021-5P Staco Energy Products Co.	MOTORIZED VRBLE TRANSF 280V 140A	0
	60M5021-6PS Staco Energy Products Co.	MOTORIZED VRBLE TRANSF 560V 84A	0
	M5011-3P Staco Energy Products Co.	MOTORIZED VRBLE TRANSF 140V 150A	0
	30M5021E-6Y Staco Energy Products Co.	MOTORIZED VRBLE TRANSF 560V 56A	0
	1510C-3 Staco Energy Products Co.	VARIABLE TRANSFORMER 280V 15A	0
	J901 Staco Energy Products Co.	VARIABLE TRANSFORMER 260V 25A	0

Equipment - Variable Transformers

1. Overview

Variable transformers are adjustable electrical devices that provide precise voltage transformation ratios for testing, calibration, and power control applications. By enabling continuous voltage adjustment between primary and secondary circuits, these transformers play a critical role in power electronics development, electrical safety testing, and industrial process optimization. Their ability to simulate real-world voltage conditions ensures their importance in modern electrical engineering workflows.

2. Main Types and Functional Classification

Type	Functional Characteristics	Application Examples
Autotransformer	Single winding with multiple taps, compact design, galvanic isolation	Motor starting circuits, voltage regulation in distribution systems
Isolation Transformer	Separate primary/secondary windings, safety isolation, noise suppression	Medical equipment testing, industrial safety systems
Multi-tap Transformer	Fixed voltage steps via mechanical switching, high precision	Transformer ratio testing, laboratory calibration
Variable AC Transformer (Variac)	Continuous sliding contact, 0-130% voltage range, manual adjustment	Prototyping, production line testing, power quality analysis

3. Structure and Components

Typical construction includes: - Core: Cold-rolled silicon steel laminations for high magnetic efficiency - Windings: Copper/aluminum conductors with thermal class F/H insulation - Adjustment Mechanism: Rotary knob or motorized actuator with precision scale - Enclosure: Powder-coated steel with thermal protection and EMI shielding - Connections: Safety terminal blocks with IP20 protection rating

4. Key Technical Specifications

Parameter	Importance
Voltage Range (0-130% V_nom)	Defines operational flexibility and test coverage
Power Rating (VA/kVA)	Determines load capacity and thermal stability
Regulation Accuracy ( 0.5%)	Impacts measurement precision and repeatability
Frequency Range (50-60Hz standard)	Dictates compatibility with different power systems
Insulation Class (F/H)	Affects safety and long-term reliability
Response Time (ms range)	Critical for dynamic voltage control applications

5. Application Fields

Key industries include: - Power Generation: Grid simulation and protection system testing - Electronics Manufacturing: Component stress testing and burn-in - Automotive: EV charging system validation - Aerospace: Avionics power quality compliance testing - Research Labs: Experimental power circuit development

6. Leading Manufacturers and Products

Manufacturer	Representative Product
Keysight Technologies	N6700 series programmable AC sources
Tektronix	ISOVOLT series isolation transformers
Fischer Elektronik	FTS 1000 transformer test systems
MEAS Switzerland	LVDT-based variable transformers

7. Selection Recommendations

Consider: 1. Voltage/power requirements with 20% safety margin 2. Adjustment resolution vs. application precision needs 3. Thermal stability in continuous operation 4. Digital interface requirements (GPIB/USB/LAN) 5. Safety certifications (IEC 61557-5, UL 61010)

8. Industry Trends

Current developments include: - Integration of IoT-enabled remote control systems - Adoption of amorphous core materials for reduced losses - Development of solid-state variable transformers (SSVT) - Increased focus on wide-bandgap semiconductor compatibility - Implementation of predictive maintenance via embedded sensors

Application Example

A semiconductor manufacturing plant uses 10kVA variable transformers to simulate voltage sags and swells during equipment qualification, ensuring compliance with SEMI F47 standards for voltage immunity requirements.