Schaffner NSG 435 Generatore
Produttore:
Modello:
NSG 435
Data:
Categoria:
Gruppo:
Descrizione:
ESD Simulator

Informazioni

Electrostatic discharge (ESD*) Under appropriate ambient conditions, both material objects and even the human body itself can become charged with electrical energy. This effect is due to "electrostatics*, a phenomenon that has been known since the earliest times. Thales von Milet (600 BC) noticed how amber attracted very light particles when it was rubbed. Touching a charged item against a conductive object leads to a charge equalisation through a spark discharge which produces a brief but powerful electro-magnetic field. This effect can be explained as follows: Two insulating substances with differing dielectric constants become charged when rubbed together, i.e. one material gives electrons to the other one. This effect is known as electrostatic charging. The same can happen to a person. When somebody walks around in a dry atmosphere on a carpet with good insulating properties, a charge of several thousand volts can be built up. If, now, that person comes close to a conductive surface, the charge that he or she is carrying flows away through a hefty spark discharge. The high equalizing current that flows, and the associated large electromagnetic field that hence results, can cause electronic devices (computers, terminals, process controllers, vehicle electronics, solid state devices, credit or memory cards, etc.) to malfunction or even be destroyed. A systematic investigation of electronic equipment and installations to determine their electromagnetic compatibility (EMC) is, today, a necessity if one is not prepared to suffer the economic disadvantages that could otherwise ensue. As a logical consequence, appropriate testing is now a legal requirement for the sale of electronic products within the EC. The ESD-test plays an important role in the range of interference sensitivity tests. It simulates frequently occurring effects and guides the development engineer to any weak spots in an instrument or item of equipment through a combination of high voltage and high frequency properties. A simulation device must be constructed so that it reproduces practical conditions realistically. Furthermore, the results obtained (interference sensitivity threshold) must be reproducible. The interference immunity of an instrument is not only dependent on its construction, it is also largely dependent on the quality or the consistency of the mass production techniques used. Knowing this has led to the demand for individual testing or at least random sample testing. Further weak spots, which could affect the overall interference immunity, can arise through the assembly of instruments into complete systems because of the installation method used, the cabling and the earthing. An ESD check on systems is therefore also prescribed. Such tests provide valuable information about the immunity of the system to effects that occur only sporadically under operating conditions and hence represent difficult to detect sources of disruption. The most significant interference components of an electrostatic discharge are of a high frequency nature. The interference paths and effects have to be assessed in the range from about 30 MHz to 1 GHz. The extremely rapid rise time of a discharge affects an object under test mostly through: - magnetic HF-coupling between electrical conductors in the electronics and the discharge current path. - electrical coupling between the discharge current and signal lines. A discharge current to the EUT flows proportionally through all the associated conductors (earth, mains, data lines, screening, etc.) according to their relative impedance. Malfunctions in insufficiently immune electronic equipment and systems make themselves apparentthrough: - program crashes - blocking of command sequences - incorrect commands, statuses or data being processed - partial system resets (e.g. only in peripheral modules which lead to errors that the system does not recognize) - disturbance or destruction of Interface chips - destruction of insufficiently protected MOS components. ESD (electrostatic discharge) testing usually shows up all the weak spots in the HF-range of a piece of equipment simultaneously. The uses to which the NSG 435 simulator can be put hence go way beyond those called for in standard-conform applications. This instrument provides the engineer with a means to detect sources of error caused by unsuitable earthing, poor ground connections, insulation problems, etc. The Generator also serves as a reliable aid for localizing hidden wiring faults during acceptance trials on installations. Use can also be made of the instrument as an insulation tester to determine the breakdown voltage of switches, relay contacts, insulators, etc.

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Manuale d'uso
Tipo di manuale:
Manuale d'uso
Pagine:
54
Dimensione:
2.98 Mbytes (3123024 Bytes)
Lingua:
english
Revisione:
ID del manuale:
601-131C
Data:
Qualità:
Documento scansionato, la lettura in parte male, non in parte leggibile.
Data caricamento:
2017 05 13
MD5:
75fc03a318b8c70e945230641324482c
Scaricamenti:
735