Information About the CCR or Carbon Composition Resistor What is a Carbon Composition Resistor (CCR)? CCR or carbon composition resistor encompasses a solid rod of conductive composition materials that can be modified to create numerous resistance values. Typically the composition of a carbon composition resistor exists of the blend of ceramic filler and carbon, the relative amount of this mix influences the resistance. The resistance value can be modified by altering the ratio of filler to conductor. There are interference-fit end caps that are connected to the rods, leads are welded to the said caps and then a specially formulated epoxy covering will be utilized to protect the resistor body. Then last of all; the resistors will be color code marked. If we will trace the historical past of CCR, we will discover that they have already been around over hundred years ago. At the beginning of the 20th century, the resistors were made without coating. As such, the lead wires were directly welded on the resistor’s body. Until the 1960’s, there initially were only two forms of resistors that are available, namely: wire-wound and carbon composition resistors. Then there has been a big change in the application of carbon composition resistors to several other types such as carbon film or metal film resistor in the 1960’s and 70s.
The Pros and Cons of CCR Probably the most significant advantage of carbon composition resistors is its capacity to resist high energy pulses. The body of the carbon composition has the capacity to dissipate the energy every time an electrical current moves through it. Let’s take the Wirewound resistors as an example. This resistor has a smaller volume of wire to dissipate the energy. Hence the thermal mass of the CCR is much higher, resulting in a higher energy pulse capacity. Carbon composition resistors can be made with a much higher level of resistance than wire wound resistors, and therefore are considerably cheaper. In terms of down sides, the qualities of CCR are actually not so good in relation to voltage dependency and load, temperature coefficient and noise. Despite of its comparatively small size, carbon composition resistors are designed for withstanding high energy pulses. For the exact same reason the carbon composition resistor continues to be utilized in lots of modern-day applications. These resistors are really great for current limiting, protection of circuits (surge and discharge protection), high power or strobe lighting, welding and high voltage power supplies.
Applications CCR are compatible with any application concerning high-energy pulses, where small size is vital. A lot of people utilize this as a viable alternative to hot moulded carbon resistors. Although many carbon composition resistors have now been substituted with other technologies (carbon-film, metal-film and wirewound particularly), these options are not always ideal, and there are still applications where carbon composition resistors are employed, generally when there are high pulse performance specifications. In many applications a resistor using a very low inductance is essential. The simplest way to acquire this is to choose a carbon composition type, where the resistive component is a homogeneous block of carbon, in order that component inductance is chiefly due to the leads. Currently, there are already ceramic-carbon types that outdated the carbon compositions that uses a carbon conductor mixed with ceramic filler rather than a hot-molded solid carbon block. Then again, the resistance value could be modified by altering the ratio of filler to conductor. Additionally, a special non-inductive metal film or foil resistors may be used more challenging requirements. Yet another application example is a medical defibrillator. Such equipment uses high energy pulses of 30 Joule. Carbon composition resistors are usually utilized in this equipment where they have to withstand the energy of the pulse.