SBW-CT

Medical special-purpose AC power supply
Introduction: The requirement of high quality mains supply for medical equipment is high. Maintaining correct incoming mains supply voltage to many types of medical imaging equipment is crucial to obtaining consistently usable exposures. Wenzhou Modern has for many years manufactured medical special-purpose AC power supply that is used to provide stable voltage to X-ray, CT and MR. The increasing sophistication of other types of medical electronics demands that attention be paid to line voltage quality if errors and inaccuracies are to be avoided. Wenzhou Modern series SBW and DBW AC power supply are well suited to such applications and are available to cover all power requirements from 1KVA to several hundred KVA. Have a look the following special features designed for medical equipment:
Features: ●   Wide input voltage ●  Adapt to any load type(resistive、capacitive、inductive) ●  No additional wave distortion, no phase deviation ●  Continually operation mode and withstand to instantaneous overload ●  Special isolation transformer can be connected at input or output terminal ●  Filtering 3 rd harmonic to acceptable level(for connected with △/Y or Y/△ isolation transformer) ●  Protection circuit(over, under voltage and over current auto shutoff after delayed) ●  Manual by-pass function ●  Vacuum pressure impregnation process for F or H insulation class ●  Lightning device addition is available as request ● Multiple output or other output voltage is available as request Technical Specification ●  Input voltage range: 220/380V, ±20%～30%, 47～60HZ ●  Nominal output voltage: Three phase, 220/380V or 230/400V ●  Over voltage cut off: When output voltage over 253V(+15%)，it will delay 4-7seconds before cut off。Automatic restart when mains voltage decrease ●  Under voltage cut off: When output voltage under 176V(-20%)，it will delay 4-7seconds before cut off。Automatic restart when mains voltage increase ●  Safe Start: The unit waits 4-7 seconds after mains restoration before output contactor is turned on. The regulator regulates the output voltage to normal output voltage before the contactor is turned on. ●  Output voltage accuracy: Selectable±1~5%，Factory preset at±2.0%, Long term stability: < 2.0 % ●  Overload protection： Automatic circuit breaker at the input 150 % overload capability for heavy start load. ●  Efficiency: ＞98%(without isolation transformer) ●  Operation environment: Temperature: -10℃～+40℃, Relative Humidity: <90%, Clean and well ventilated ●  Capacity: Single phase: 10KVA～50KVA, Three phase: 10KVA～150KVA Composition and Operation Principle: SBW、DBW Series AC power supply is consist of compensation transformer、contact variable auto transformer、isolation transformer(and without isolation transformer)、voltage detection and control circuit、over voltage and under voltage protection circuit、servo-motor and driving mechanism.
Refer to Fig U2=U1±△ U as U1—Input voltage U2—output voltage, △U—compensate voltage When Input voltage and load is varied the output voltage is varied respondly,the acqusition comparator control circuit sense from output, after rectifier、filter and compared with reference voltage, as the signal is higher than the upper limit ref. Value, energy the motor to drive and move the brush along the auto-transformers conducting surface, thus change the compensated voltage of compensated transformer, and adjusts the output voltage to reach within the range. If lower than the lower limit ref.Value, the motor is rotated at opposite wise and stabilize the output voltage too.