EoW July 2014

News Technology

How is the conductor temperature measured on a non-contact basis?

shielded modules of at least category 6A (RJ45 and PS-GG45) and Dätwyler’s new RJ45-IEC adapter are needed to allow the use of a single standard cabling system for every type of transmission and service including cable television. One of these adapters takes care of the supply of coaxial services to the data network at the patch panel, the other is plugged into the data socket to allow TV sets to be connected. The adapter transmits using common mode and provides an IEC connector as the usual physical interface. Dätwyler Cabling Solutions – Germany Website : www.cabling.datwyler.com By means of the reference radiator, the conductor is ‘brightened’ and consequently the sum of the actual temperature radiation and the reflected radiation equals 1. Thus, a thermal image camera measures precisely the temperature of the conductor. Sikora AG – Germany Website : www.sikora.net and transmission (t) of a body equals 1. Assuming that a metallic conductor has no transparency, even in the infrared range (ie that it is not transparent), the radiation law can be simplified to: e+r=1 From this formula it can be seen that the part of a hot conductor does not emit temperature-related radiation to the environment, but it can reflect thermal radiation. Therefore, the non-contact temperature measuring device Wire-Temp 6000 from Sikora for the measurement of the conductor temperature is equipped with a reference radiator.

A data network can be used for voice and data transmission, for the remote supply of power to end devices, and even for digital cable television. Dätwyler has introduced its universally applicable ‘dual-mode’ cables and the new RJ45-IEC adapter – a solution which fits the bill, giving the user the ultimate in flexibility and at the same time saving money and resources. Unlike most commercially available copper data cables, Dätwyler’s high-performance category 7A data cables – types CU 7150 4P and CU 7120 4P, for example – allow two different This is, for example, the case at so called ‘black bodies’. This problem also occurs when the temperature of copper or aluminium conductors are to be measured, for example, to precisely measure and control their temperature high-performance copper By using a thermal image camera, it is possible to determine the intensity of the thermal radiation of objects. A very easy and clear application is, for example, the determination of a building’s heat emission. In areas where much heat is lost, ie where much heat is emitted, the heat is correctly recorded by the thermal image camera and usually shown as a false colour image. For the measurement of the temperature of an object, the emission of the object has to be known. This value is approximately known, but can often be subject to variations. It is easier to determine the temperature of an object when its emission approaches e=1.

with the help of a preheating device. The emission level of a drawn copper wire varies depending on the surface quality between e=0.04 and 0.2. ▲ ▲ Thermal Image Camera: The orange area of the thermal image shows the temperature of the reference radiator as well as the conductor, which is running in the middle. In the false colour image, the conductor temperature appears yellow and, therefore, has a higher temperature in relation to the reference radiator

The radiation law: e+r+t=1 states that the emission (e) plus the reflection (r)

Premium quality dual-mode cables

modes of transmission: ‘differential mode’ for symmetrical signal transmission and ‘common mode’ for coaxial signal transmission. These dual-mode cables are therefore universally suitable for transmitting speech, for the transmission of data at a rate of up to 10 gigabits per second (10GBit/s), of BC signals for digital cable TV up to 862 megahertz and, not least, for the remote supply of power to end devices (Power over Ethernet, eg PoE+). This gives the user the best possible flexibility, saves resources and cuts installation costs.

In addition to the dual-mode cables,

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July 2014