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Power Rectifier Diode Д122 Series (D122 Series)

Power rectifier diodes of the D122 series are stud diodes designed for general-purpose applications, capable of converting both direct and alternating currents up to 40A (depending on the series) with a frequency of up to 500 Hz in circuits with voltages ranging from 100V to 1600V. The polarity of the diode is identified by an icon on the case. In the case of direct polarity, the diode’s base is the anode, and the stud terminal is the cathode. Conversely, for reverse polarity, this relationship is reversed, and the marking includes the letter “X.”

The diodes of the D122 series feature the SD2 case type with an M6 thread and a weight of 12g. Notable type designations for the D122 series include D122-32, D122-32X, D122-40, and D122-40X. For effective heat dissipation, these diodes are assembled with coolers (heat sinks) using threaded connections. To ensure reliable thermal and electrical contact between the diode and the cooler during assembly, it is crucial to adhere to the specified tightening torque (M2). Additionally, heat-conducting paste can be applied during assembly for enhanced heat dissipation.

D122 power diodes find application as rectifying and demagnetizing diodes, mitigating the adverse effects of switching overvoltages. They are commonly utilized in low-voltage rectifiers for welding and galvanic equipment, uncontrolled or semi-controlled rectifier bridges, and electric generators for industrial and transport applications. Manufactured to withstand temperate, cold (UHL), or tropical (T) climates, these diodes fall under accommodation category 2.

Diode Normal/Reverse Polarity

LJD 12240 X16 UHL2 

  • LJ-MD 
  • Д Diode
  • 122 Series 
  • 40  Maximum permissible on-state current in amperes
  • X Polarity Identification: “X” denotes reverse; absence indicates normal polarity
  • 16 Class designation based on repetitive reverse voltage in hundreds of volts
  • UHL2 Class designation based on repetitive reverse voltage in hundreds of volts

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From high surge current capability to precise power control, our diodes and thyristors offer exceptional features that cater to your specific needs. Whether you require efficient rectification, fast switching, or precise phase control, our products deliver reliable and precise results.


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