Prerna Electronics

Due to the excellent speed torque characteristics and simplicity in Control, DC Motor is a natural choice for speed controlled electrical drives. The reliability of DC Motor drives depends on the commutating quality. Sparkless commutation can be achieved only with smooth DC voltage applied to Armature winding. Considering the above mention points, our controllers have following features :

• Many models to choose from simple ON/OFF Control to modulating motor or valve controllers ; Single Set Point to Triple Set Point, Stepless Controllers.
  

• Automatic cold junction compensation with wide variety of temperature spans from -50°C to + 1200°C.
  

• High Impedance input with thermocouple break protection.
  

• Isolated Relay change over contact for 3A/250V AC or SCR gate outputs available.
  

• Adjustable band width for various process.
  

• Analog or digital thumb wheel switch set point.

• Presettable with digital thumb wheel switch for speed trip.
  
• Digital display of R.P.M. or calibrated according to the line speed of machine.
  
• Solid State input signal from Proximity Switch, Optical Sensor or Rotary Encoder are acceptable for :
  High = +6V DC to +24V DC,
  Low = 0 to +2V DC with minimum pulses width of 0.5m.sec.
  
• Available with pluge in octal base connecting socket or with screw termination.
  
• Resolution of 1 to 9999 R.P.M.
  
• Dual Wheel type Encoder for machine speed measurement.
  
• Flange mounting Encoder for feedback & counting.

• Our design will give efficient energy conversion more than 85% of input power into heat.

• Fast warm-up (within seconds) saves energy.

• Localised heat : by applying heat at a selected area saves energy and money

• Length, width & capacity design as per the Clients requirement.

• Solid State Analog or Digital with and without display.
• Power ON Reset or Manual Reset push button on front Panel.
• Wide Ranges : from 0.01 second to 99 hours.
• ON or OFF delay with accurate quartz crystal time base counting system.
• Isolated Relay change over contact for 3A/250V AC.
• Up or Down count are available in digital timers.
• Available in :
  1) ABS Plastic Cabinet Size : 72 X 72 X 150 mm (H X W X D)
  Panel cutout Size : 68 X 68 mm.
  2) ABS Plastic Cabinet Size : 96 X 96 X 150 mm (H X W X D)
  Panel cutout Size : 92 X 92 mm.

• 6 Digit Two Set Point Programmable non-volatile memory with micro controller.
• 4 Digit Single, Double & Triple Set Point without memory.
• High counting speed upto 5000 pulses per second.
• Power ON Reset, Auto and Manual reset with push button
• Backup power supply function for one week memory protection is available.
• Isolated Relay change over contact for 3A/250V AC or Solid State 24V/3A DC output to operate Clutch and Brake.
• Power supply to external sensor upto 18V DC ± 10%, 20MA.
• Solid State input signal from Proximity Switches, Optical Sensor or Rotary Encoder are acceptable with :
  High = +6V to +24V DC,
  Low = 0 to +2V DC; minimum pulses width of 0.5m.sec.
• Available in :
  1) ABS Plastic Cabinet Size : 72 X 72 X 150 mm (H X W X D)
  Panel cutout Size : 68 X 68 mm.
  2) ABS Plastic Cabinet Size : 96 X 96 X 150 mm (H X W X D)
  Panel cutout Size : 92 X 92 mm.
  3) 24V DC CLUTCH/BRAKE Panel Mounting Counter.
  Size : 190 X 140 X 230 mm (H X W X D)
  Panel cutout Size : 163 X 123 mm (H X W)

The specially designed Contactless Sensor is an adjacent measuring thermocouple designed for measurement of surface temperature of moving or rolling materials such as Heating rollers, Press rollers, running sheets, paper, film etc...

The operating life of the heater's element will reduce by a rapid temperature fluctuation or power fluctuation. It's therefore advisable to choose an electric control equipment which gives as even temperature as possible like thyristor control system.
Our Heater Power Control Units from 100W to 500KW with thyristorised control will:

• Control energy output can be adjusted to match the process requirement.
• Normally Heater capacity will be always more. To match the heat output to process requirement, voltage to the heater 0 - 100% can be set with the controller.
• Controllers applies power to the heater gradually which limits inrush current to heaters.
• Variable heat density ; heating rate can be adjusted by varying heater voltage through this controller.
• Potentiometric power setting can also be achieved by Remote push button.
• Available for 1Ø, 230V AC, 50Hz input supply & 3Ø, 440V AC, 50Hz input supply (4 wire system).

Years of our experience on machineries used in paper, rubber, plastics and textile processes our winding machine drives with adjustable winding characteristics meet tension control requirements of the products.