Unlike fixed ratio transformers, Setavolt® ‘Variac’ style Three Phase auto-transformers provide an infinity variable step-less output voltage that can be adjusted from 0 to 117% of the nominal input voltage.
SA-3 Series Models are available in 11 different power ratings:
3, 5, 10, 15, 20, 25, 30, 35, 40, 50 & 60 Amps
and support nominal input voltages of 380 to 415V (HB Range) and 190 to 208V (LB Range) and 440 to 480V (HB-480 Range).
Offered as manually operated and supplied as standard in IP20 (NEMA 1 Style) enclosures, with terminal covers, the casings can be easily removed for ‘Open’ style and panel mount applications.
To learn more please check out the listings below –
The basic variable auto-transformer consists of a copper winding on a toroidal core of laminated, grain-oriented, silicon steel. A carbon brush, connected to an output terminal, is rotated over the length of a precision-ground, commutator track to tap off voltage at any turn from zero volts to the maximum output voltage of the winding.
Unlike a standard fixed ratio transformer, Setavolt® variable transformers are designed to provide an infinitely variable step-less output voltage that can be adjusted from 0 to 117% of the transformer’s nominal input voltage.
Design Features
High Efficiency & Excellent Regulation
In contrast to current hungry rheostats and other resistive type voltage controllers, Setavolt® variable auto-transformers have an extremely small power loss, delivering efficiency of 98% or better. Within the transformer ratings, our variable transformers deliver, from no-load to full-load current, negligible variation in output voltage.
Distortion Less Voltage Control
Due to the superiority of the core design and quality of the steel grade utilized, Setavolt® Variable Transformers provide a facsimile of the input waveform with negligible distortion – an essential feature required by many electronic applications.
Low Operating Torque
Due to the ultra-smooth commutator surface, correct and constant contact pressure of the brush on the commutator, combined with the firm positioning of the coil and internal components ensures all Setavolt® Variable Transformers deliver a low operating torque.
Trouble-Free Mechanical Construction for Long Life
All Setavolt® variable transformers are designed for heavy-duty and trouble-free operation. Built to exacting mechanical tolerances, using the finest materials available, the quality of design and build ensures minimal maintenance requirements and enhanced design life.
Negligible Maintenance
When operated in accordance with the operating instructions, the only component that may require periodic inspection and occasional replacement are the brushes. As the brushes are made of a special highly endurable carbon and the design ensures proper contact with the commutator at all times, the need for replacement is infrequent.
Straight forward Install & Use
Whether for bench use or panel mounting, installation, mounting, and use is designed to be easy. Terminals are easily accessible – screw or lug. Output, on manually operated variable transformers, is controlled by either clockwise or anti-clockwise knob rotation.
International Standards Compliance & CE Certification
All Setavolt® variable transformers are designed and manufactured to comply with all relevant International Standards and appropriate European Union CE Directives.
Note: Other voltage configurations available on request/quotation.
Ratings: Currents stated are the maximums at any voltage within the stated output voltage range. Should it be required to run the variable transformer continuously at this current, then we would recommend you select a model with a 20% excess rating (eg for a 20 Amp continuous rating select the 25 Amp model).
Note: Other voltage configurations available on request/quotation.
Ratings: Currents stated are the maximums at any voltage within the stated output voltage range. Should it be required to run the variable transformer continuously at this current, then we would recommend you select a model with a 20% excess rating (eg for a 20 Amp continuous rating select the 25 Amp model).
Note: Other voltage configurations available on request/quotation.
Ratings: Currents stated are the maximums at any voltage within the stated output voltage range. Should it be required to run the variable transformer continuously at this current, then we would recommend you select a model with a 20% excess rating (eg for a 20 Amp continuous rating select the 25 Amp model).
Continuously variable from 0 to 117% of the input voltage
Frequency:
47 to 65Hz
Power Factor:
The Power Factor has no effect on performance providing the variable transformer is being used within its rated capacity
Efficiency:
≥98%
Surge Rating:
4 x max. current rating for 1 second 3 x max. current rating for 3 seconds 1.5 x max. current rating for 15 seconds
Environmental:
Temperature range -15 to 45°C. Derate by 2% for each additional °C up to a max of 60°C Suitable for indoor tropical use up to 95% RH (non-condensing) Maximum altitude 1000m. Derate by 2.5% for each additional 500m
Standards Compliance:
BS EN 61558-1:2005 + AI:2009 & BS EN 61558-2-13:2009
CE Conformity:
CE Marked – compliant with European Union Directive 2006/95/EC (Low Voltage Directive)
RoHS Compliance:
Fully RoHS Compliant – complaint with European Union Directive 2011/65/EC (RoHS Directive)
Standard Warranty:
1 Year / 12 months from date of supply
Note:Safety Caution: When using variable transformers, installation and connection must be carried out in accordance with relevant safety standards, and care must be taken to ensure local regulations are strictly adhered to. When utilized as components in other systems, the variable transformers must never be used without suitable safety protection being in place.
Operator Manual with sections on installation, and maintenance.
CE Certification
SA-3 Series Three Phase Manually Operated Variable Transformers comply with the relevant European Union (EU) health, safety, and environmental protection directives and regulations and are duly CE marked.
Sinalda UK Declaration
Low Voltage Directive – 2006/95/EC
Sinalda UK Declaration
RoHS Directive – 2011/65/EC
If you do not find the Variable Transformer that meets your application’s exact needs, please contact us with your specific detailed requirements.