Electronic Components Blog

Wednesday, 24 September 2014 14:09

Pulse - Surge Capability of Resistors


Due to existing needs, many modern electronic circuits and apparatus experience transient pulses and surges. This in turn has led to the need to "design in" transient surge protection especially in circuits like motor controllers.

When a motor starts, the current drawn at this point is excessive and can cause failure in resistors. Similarly if capacitors are used for motor starting, the current – limiting resistors in the circuit experience very high overloads during the capacitor charge / discharge cycles.

At this point it is pertinent to mention that while there is a plethora of information available on this subject for active devices like semiconductors, passive devices such as resistors are often neglected and their role in withstanding transient pulses/surges is not yet fully grasped by the designer.

Since resistors are often located in areas likely to experience transient pulses / surges, it is indeed critical for the designer to be fully aware of this phenomenon and design in the correct resistors for his particular application. HTR has worked closely with designers to produce custom built resistor solutions for specific protection applications and a summary of information / data obtained over the years is now given in the attachment for the benefit of the design engineer.

Related Solutions

  • Low profile braking resistor, optimized design for high energy to heat conversion

    When designing a motor controller, which has to be as compact as possible, every engineers challenge is to deal with the heat dissipation which is being generated when braking the motor. Using the BRK-series of Isabellenhütte as a braking chopper, you're able to resist high energy loads. It's ideal for use on Inverters, EV pre-charging & current limiting applications.

  • Ideal precision shunt for extreme conditions

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  • Isabellenhütte achieves record current measurement on shunt basis

    30,000 amperes measured, 100,000 amperes next target!

    Isabellenhütte Heusler GmbH & Co. KG, Hesse, Germany, has made inroads into the high-current range of industrial applications with shunt current measurement. The measurement of currents of up to 30,000 amperes using low-ohmic shunts can truly be seen as unique. Moreover, the company's next target is 100,000 amperes.


  • Hi-Tech Resistors (HTR)

    Hi Tech Resistor Pvt. Ltd. was established in 1986 as a specialist manufacturer of standard fixed wire wound resistors with basic technology aquired from Samsung Co. Ltd. HTR transformed itself into a modern and broad based manufacturer of wire wound resistive products, with state-of-the-art design and testing capabilities which are comparable with the best of the world.

Related Blog messages

  • A new range of Electron Beam Welded, low ohm current sense resistors at HTR

    At this years Electronica, from November 11th until November 14th in Munich, HTR takes pride in introducing a new range of Electron Beam Welded low ohm/ current sense resistors. These resistors or shunts are very much on the cutting edge of developing resistor technology and these type of resistors might be a replacement for similar resistors made by Vishay.

  • HTR Resistor finder App

    HI-TECH RESISTORS PVT. LTD, popularly known as HTR in the electronics industry worldwide, is a highly innovative manufacturer of wire wound and low ohm current sense resistors.

    To show that HTR is not only innovative in the production of resistors, they have introduced an App "The HTR Resistor Finder". This App is already available to users of smart phones on Android technology and can be downloaded free from the App store today.


    HTR an ISO/TS 16949 : 2009 Certified manufacturer has received UL Certification as per UL 1412 (HTR file #E342534) for their range of safety fusible Wire Wound Resistors. These devices are manufactured using specially selected wires which are wound on thermally efficient ceramic body & welded to end caps thus creating a fully welded product for 100% reliability.