Cable coupler

Figure 6.81 Flameproof plug-and-socket connectors ( cable couplers ), fitted into a flameproof enclosure (EEx dl equipment for coal mines).

Plug-and-socket connectors, cable couplers, see Fig. 6.81. These parts are inserted into an opening of the flameproof enclosure and act as a flameproof seal. This also applies to the unplugged state of plug and socket. Such means are favoured where apparatus is frequently removed, e.g. in coal mines (Group I application). 

High voltage incoming line via cable coupler to switching cabinet. 

However, all necessary system components such as cables, couplers, sources, demodulation units, require reflection with regard to reliability and stability, especially, when standard fiber sensor components are modified according to specific requirements or for critical application [59-62]. Users of measurement systems want to be definitely sure that a chosen sensor system is suitable and reliable for the specific intended use. A very useful method is the vahdation procedure of a measurement system or of components of it because they then get assured information about performance and limitations of a sensor system. Then they are able to draw feasible conclusions. Vahdation is explained in the international standard ISO/IEC 17025 of the International Standardization Organization (ISO) [63]. According to this standard, validation is the confirmation by examination and the provision of objective evidence that the particular requirements for a specific intended use are fulfilled. 

Type of protection EEx dl Certificates - Plug MECS 93 C 5502 U Socket MECS 93 C 5503 U Plug coupler MECS 93 C 5504 Rated voltage 1100V 3 AC Rated current 300 A Cable conductor cross-section up to 120 mm2. 

Zhong, L. Chen, G. Xu, Y. A novel calibration method for PD measurements in power cables and joints using capacitive couplers. Meas. Sci. Technol. 2004, 15, 1892-1896. 

Fiber optics may be used as probes for conventional spectrophotometric and fluorescence measurements. Light must be transmitted from a radiation source to the sample and back to the spectrometer. While there are couplers and designs that allow light to be both transmitted and received by a single fiber, usually a bifurcated fiber cable is used. This consists of two fibers in one casing, split at the end that goes to the radiation source and the spectrometer. Often, the cables consist of a bundle of several dozen small fibers, and half are randomly separated from the other at one end. For absorbance measurements, a small mirror is mounted (attached to the cable) a few millimeters from the end of the fiber. The source radiation penetrates the sample solution and is reflected back to the fiber for collection and transmission to the spectrometer. The radiation path length is twice the distance between the fiber and the mirror. 

Movement of railcars and trucks within plants is frequently done by carrier crews. Since, however, plant production schedules and availability of railroad switch crews are often not compatible, many plants provide their own switching service. Specially built prime movers that can operate on both roads or rails are available. Front-end loaders can be equipped with couplers to permit car movement. Cable-operated car pullers are now generally in disfavor because of lack of control of cars being moved. Trailers are often moved by tractors especially equipped with an adjustable fifth-wheel coupling, which will couple to any trailer regardless of the height of its cou-pling. 

After successfiilly passing all required static tests, Glasshopper 1 was subjected to a series of impact tests. For these tests, the car that was fully loaded, was pulled by cable up an inclined ramp and released to impact another fully loaded standing car that had its brakes released. Velocity of the car at impact was controlled by its height on the ramp at the time of release. Car s velocity was incrementally increased until an experimentally measured coupler force of 113,500 kg (250,000 lb) was developed during the impact. 

Exempt. Components meeting flammability requirements of relevant lEC component standard, certain wire insulation (PVC/TFE/PTFE/FEP/ Neoprene), small parts mounted on V-1 material (I/Cs, transistors, opto-couplers, capacitors, etc.), one or more layers of insulation (adhesive tape, etc.), individual clamps, heat-resistant glass, nameplates, mounting feet, keycaps, knobs, lacing tape, twine, cable ties, ceramic materials, metals, others. 

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