In this article we compare two of the most common resistor styles for electric power resistor programs, Wirewound design and thick movie engineering.
Regardless of the development the most important layout criteria when creating any electric power resistor are:
- The resistor worth
- The essential electrical power dealing with functionality
- Resistance stability after a while
- Improve in resistance worth with temperature
In almost any large power software temperature effects as well as resistor ability managing capability are the primary things to consider. The supplies and strategies utilized to build the resistor has a direct effect on its long run functionality and security.
Resistor Development
The resistor layout and design incorporates a immediate influence on its long run stability and efficiency. Full resistance is decided through the resistivity of your resistor content, and also the resistor monitor size, width and thickness. You'll find noticeable limits with whatever resistor product is preferred. For thick film resistors even though it is achievable to raise observe duration and width major will increase in thickness are not possible in addition to a restricted range of material resistivity can be found. For wirewound expanding either the wire thickness or size has An important impact on the size of the resistor.
The long run security of the resistor substance along with the effect of temperature will also be important factors. Temperature results can degrade the resistor overall performance or, in Excessive circumstances, cause resistor failure. Within the thick movie resistors temperature consequences could resistors be minimized by selecting an proper thickness of a suitable substrate content. For Wirewound resistors the development, Main substance, the wire variety and diameter, the all need cautious thing to consider.
Comparing Resistor Systems
The important thing benefits of thick film power resistors in excess of Wirewound are lesser size, can be found at appreciably decreased Expense (together with tooling Value), have lessen inductance and enhanced thermal management. Thick film resistors are for that reason smaller, Have got a more quickly frequency response and are far better suited to heat sinking applications. Thick movie technology also provides bigger resistance values and higher voltage score than Wirewound resistors.
The most important benefit of thick film technologies in significant energy apps is definitely the high thermal conductivity of your ceramic (Alumina) substrate making it ideal for applications in which higher energy dissipation is needed in a small region. The substrate product usually means it is a wonderful match Along with the aluminium materials in heat sinks which is chemically inert and mechanically stable.
Conclusion
Despite the fact that Wirewound resistors do provide better precision (enhanced tolerance), higher steadiness and decreased values it is usually for the price of much larger footprint and higher inductance than an equivalent thick movie system. Any Wirewound resistor is basically a coil of wire (an inductor) and Despite the fact that alternative of material can limit the affect of your substantial inductance it remains A significant disadvantage. The coil building also helps make warmth dissipation a major problem.