Ramson Variacs are continuously variable voltage autotransformer, having movable carbon tip, fixed to a brush arm sliding on a silver plated commutator. Rotation of the brush arm by either by manual or motor drive, delivers an output voltage from zero to or above line voltage. 
 

Applications:

• Voltage and current control in development and experimental work.
• Over and under voltage testing of electrical and electronic equipment.
• Heat control of ovens, furnaces, Infra red Heaters etc.
• Testing and calibration of Voltmeters, Ammeters, Wattmeters etc.
• Built in as a integral control element in electrical, electronic and automatic control and process equipment.
• Supply voltage adjustment, boosting of low lines and line voltage stabilisation, either manually or automatically in automatic voltage stabilisers.
• Lighting control in theatres, auditoriums, hotels, restaurants,  photographic studios and darkrooms, etc
• Motor speed control either direct or through suitable circuits
• control of DC Voltage and current through rectifiers. Control of rectifiers in electroplating etc.

• Single Phase Flush Type Model

• Single Phase Portable Model

• Three Phase Open Type Model

• Three Phase Portable Model

• Three Phase Oil Cooled Model

Amps: 2, 3, 4, 6, 8, 10, 15, 20, 28 (available in Open & Enclosed models)
 
Amps: 40, 50, 60, 75, 100, 150, 200, 300, 400, 500 & 600
           (available only in oil cooled Model)

•  Rugged Construction : Ramson Vairacs are designed for heavy duty trouble free operations. All components are designed to give maximum life to the unit under extreme operating conditions. You would also find them compact and sturdy.

• Excellent Regulation: The drop in voltage from "no load" to "full load" is minimal in our variacs.

•  High Efficiency : Careful copper core selection and design assures the user of low watt loss as compared to other type of controllers.

•   No wave form Distortion: Our Variacs provides an output voltage waveform which is a faithful and distortionless replica of the input voltage wave form.

•  Silver plated commutator:  A Special silver plating technique is used on the commutator, enabling it to withstand high overloads and maintain constant contact drop. It also ensures smooth operation, long life and increased resistance to corrosion.

•   Overload Capacity: Because of its careful designing, our variacs can withstand many overloads.

•  Low Operating Torque: A Glass smooth commutator, special sintered bushings for the shaft and perfect assembling of the coils, result in low operating torque for our auto-transformers.

•  Smooth and Linear output: As voltage between turns is small and as the brush arm is in constant contact with more than one turn, harmful sparking is avoided and output can be set very easily to a fraction of a volt from zero onwards by rotation of the knob.

•   Low Magnetic Current: By using an adequate section of the high quality grain oriented silicon sheel, the iron losses are controlled to the minimum. The no load current is invariably less than 3% of the rated current.

•  Negligible Maintenance and Trouble Free Long Life: Ramson Variacs  have been designed to guarantee performance. Therefore no special care need be taken in normal working conditions.  Timely replacement of carbon tips and cleaning of the commutator surface of foreign particles and accumulated dust will ensure a considerably long, maintenance free and uninterrupted life to the unit.

Home        DC Motors        Motor Controls        Catalogue        Rheostats        Education