safety+laws

   1) The Knowledge of Ourselves

   We come therefore now to that knowledge whereunto the ancient oracle directeth us, which is the knowledge of ourselves; which deserveth the more accurate handling, by how much it toucheth us more nearly. This knowledge, as it is the end and term of natural philosophy in the intention of man, so notwithstanding it is but a portion of natural philosophy in the continent of nature.... [W]e proceed to human philosophy or Humanity, which hath two parts: the one considereth man segregate, or distributively; the other congregate, or in society. So as Human philosophy is either Simple and Particular, or Conjugate and Civil. Humanity Particular consisteth of the same parts whereof man consisteth; that is, of knowledges which respect the Body, and of knowledges that respect the Mind... how the one discloseth the other and how the one worketh upon the other... [:] the one is honored with the inquiry of Aristotle, and the other of Hippocrates. (Bacon, 1878, pp. 236-237)

   2) As a Science, Psychology Is Distinct

   The claims of Psychology to rank as a distinct science are... not smaller but greater than those of any other science. If its phenomena are contemplated objectively, merely as nervo-muscular adjustments by which the higher organisms from moment to moment adapt their actions to environing co-existences and sequences, its degree of specialty, even then, entitles it to a separate place. The moment the element of feeling, or consciousness, is used to interpret nervo-muscular adjustments as thus exhibited in the living beings around, objective Psychology acquires an additional, and quite exceptional, distinction. (Spencer, 1896, p. 141)

   3) Psychology Can Never Be an Exact Natural Science

   Kant once declared that psychology was incapable of ever raising itself to the rank of an exact natural science. The reasons that he gives... have often been repeated in later times. In the first place, Kant says, psychology cannot become an exact science because mathematics is inapplicable to the phenomena of the internal sense; the pure internal perception, in which mental phenomena must be constructed,-time,-has but one dimension. In the second place, however, it cannot even become an experimental science, because in it the manifold of internal observation cannot be arbitrarily varied,-still less, another thinking subject be submitted to one's experiments, comformably to the end in view; moreover, the very fact of observation means alteration of the observed object. (Wundt, 1904, p. 6)

   4) How a " Mathematical" Psychology May Be Realized in Practice

   It is [Gustav] Fechner's service to have found and followed the true way; to have shown us how a "mathematical psychology" may, within certain limits, be realized in practice.... He was the first to show how Herbart's idea of an "exact psychology" might be turned to practical account. (Wundt, 1904, pp. 6-7)

   5) The Rights of Psychology as Science

   "Mind," "intellect," "reason," "understanding," etc. are concepts... that existed before the advent of any scientific psychology. The fact that the naive consciousness always and everywhere points to internal experience as a special source of knowledge, may, therefore, be accepted for the moment as sufficient testimony to the rights of psychology as science.... "Mind," will accordingly be the subject, to which we attribute all the separate facts of internal observation as predicates. The subject itself is determined p. 17) wholly and exclusively by its predicates. (Wundt, 1904,

   6) The Study of Animal Psychology

   The study of animal psychology may be approached from two different points of view. We may set out from the notion of a kind of comparative physiology of mind, a universal history of the development of mental life in the organic world. Or we may make human psychology the principal object of investigation. Then, the expressions of mental life in animals will be taken into account only so far as they throw light upon the evolution of consciousness in man.... Human psychology... may confine itself altogether to man, and generally has done so to far too great an extent. There are plenty of psychological text-books from which you would hardly gather that there was any other conscious life than the human. (Wundt, 1907, pp. 340-341)

   7) The Behaviorist's Formulation

   The Behaviorist began his own formulation of the problem of psychology by sweeping aside all medieval conceptions. He dropped from his scientific vocabulary all subjective terms such as sensation, perception, image, desire, purpose, and even thinking and emotion as they were subjectively defined. (Watson, 1930, pp. 5-6)

   8) Man Is a Microcosm

   According to the medieval classification of the sciences, psychology is merely a chapter of special physics, although the most important chapter; for man is a microcosm; he is the central figure of the universe. (deWulf, 1956, p. 125)

   9) Brief Overview of Psychology's History

   At the beginning of this century the prevailing thesis in psychology was Associationism.... Behavior proceeded by the stream of associations: each association produced its successors, and acquired new attachments with the sensations arriving from the environment.

   In the first decade of the century a reaction developed to this doctrine through the work of the Wurzburg school. Rejecting the notion of a completely self-determining stream of associations, it introduced the task ( Aufgabe) as a necessary factor in describing the process of thinking. The task gave direction to thought. A noteworthy innovation of the Wurzburg school was the use of systematic introspection to shed light on the thinking process and the contents of consciousness. The result was a blend of mechanics and phenomenalism, which gave rise in turn to two divergent antitheses, Behaviorism and the Gestalt movement. The behavioristic reaction insisted that introspection was a highly unstable, subjective procedure.... Behaviorism reformulated the task of psychology as one of explaining the response of organisms as a function of the stimuli impinging upon them and measuring both objectively. However, Behaviorism accepted, and indeed reinforced, the mechanistic assumption that the connections between stimulus and response were formed and maintained as simple, determinate functions of the environment.

   The Gestalt reaction took an opposite turn. It rejected the mechanistic nature of the associationist doctrine but maintained the value of phenomenal observation. In many ways it continued the Wurzburg school's insistence that thinking was more than association-thinking has direction given to it by the task or by the set of the subject. Gestalt psychology elaborated this doctrine in genuinely new ways in terms of holistic principles of organization.

   Today psychology lives in a state of relatively stable tension between the poles of Behaviorism and Gestalt psychology.... (Newell & Simon, 1963, pp. 279-280)

    10) Psychological Research Is Not Building toward Systematic Clarity

   As I examine the fate of our oppositions, looking at those already in existence as guide to how they fare and shape the course of science, it seems to me that clarity is never achieved. Matters simply become muddier and muddier as we go down through time. Thus, far from providing the rungs of a ladder by which psychology gradually climbs to clarity, this form of conceptual structure leads rather to an ever increasing pile of issues, which we weary of or become diverted from, but never really settle. (Newell, 1973b, pp. 288-289)

    11) Psychology as a Scientific Discipline

   The subject matter of psychology is as old as reflection. Its broad practical aims are as dated as human societies. Human beings, in any period, have not been indifferent to the validity of their knowledge, unconcerned with the causes of their behavior or that of their prey and predators. Our distant ancestors, no less than we, wrestled with the problems of social organization, child rearing, competition, authority, individual differences, personal safety. Solving these problems required insights-no matter how untutored-into the psychological dimensions of life. Thus, if we are to follow the convention of treating psychology as a young discipline, we must have in mind something other than its subject matter. We must mean that it is young in the sense that physics was young at the time of Archimedes or in the sense that geometry was "founded" by Euclid and "fathered" by Thales. Sailing vessels were launched long before Archimedes discovered the laws of bouyancy [ sic], and pillars of identical circumference were constructed before anyone knew that C IID. We do not consider the ship builders and stone cutters of antiquity physicists and geometers. Nor were the ancient cave dwellers psychologists merely because they rewarded the good conduct of their children. The archives of folk wisdom contain a remarkable collection of achievements, but craft-no matter how perfected-is not science, nor is a litany of successful accidents a discipline. If psychology is young, it is young as a scientific discipline but it is far from clear that psychology has attained this status. (Robinson, 1986, p. 12)

 

увеличение температуры внутри НКУ
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[Интент]

Параллельные тексты EN-RU

Temperature-rise inside assemblies

An excessive temperature-rise inside assemblies represents one of the main problems which are often subject for discussion and to which users pay the most attention.

It is evident that an anomalous heating inside switchgear can jeopardize the safety of people (possible fires) and plants (malfunctioning of the apparatus).

For this reason, the Standard IEC 60439-1 gives a lot of space to the permissible temperature-rise limits in an assembly and to the methods to determine such limits either directly as type test or by analytic extrapolation.

The term type test defines the tests intended to assess the validity of a project according to the expected performances.

Such tests are usually carried out on one or more prototypes and the results of these type tests are assumed to obey to deterministic laws.

Therefore these results can be extended to all the production, provided that it complies with the design of the tested samples.

The type tests prescribed by the Standard IEC 60439-1 include:
• verification of temperature-rise limits
• verification of the dielectric properties
• verification of the short-circuit withstand strength of the main circuits
• verification of the short-circuit withstand strength of the protective circuit
• verification of the effective connection between the exposed conductive parts and the protective circuit
• verification of clearances and creepage distances
• verification of mechanical operation
• verification of the degree of protection

As said above the verification of temperature-rise limits is one of the most critical aspect for an assembly;

the Standard states the temperature-rise limits referred to an average ambient air temperature of ≤35°C which the switchgear complying with the Standard must not exceed (Table 1).

[ABB]

Увеличение температуры внутри НКУ

Чрезмерное увеличение температуры внутри НКУ свидетельствует о наличии одной из основных проблем, часто являющихся предметом рассмотрения, и на которые потребители обращают наибольшее влияние.

Совершенно очевидно, что аномальный нагрев элементов внутри НКУ может создать опасность для людей (например, возникновение пожара) и для электроустановки (неправильная работа аппаратуры).

Поэтому стандарт МЭК 60439-1 уделяет большое внимание рассмотрению предельных значений температуры в НКУ и методам их определения, как путем проведения прямых испытаний, так и с помощью экстраполяции значений, полученных в результате испытаний.

Термин типовые испытания определяет испытания, целью которых является доказательство, что испытываемое устройство отвечает определенным техническим условиям.

Такие испытания обычно проводят на одном или нескольких типопредставителях, и считают, что полученные результаты являются детерминированными.

Поэтому их можно применить ко всем изделиям, конструкция которых соответствует испытанным образцам.

В перечень проверок и испытаний, проводимых на НКУ в соответствии со стандартом МЭК 60439-1, входят:
• проверка предельных значений превышения температуры;
• проверка диэлектрических свойств;
• проверка прочности при коротких замыканиях
• проверка прочности при коротких замыканиях цепи защитного заземления
• проверка прочности соединения открытых проводящих частей и цепи защитного заземления
• проверка воздушных зазоров и длин путей утечки;
• проверка механической работоспособности
• проверка степени защиты

Как сказано выше проверка предельных значений превышения температуры является одним из наиболее важных параметров НКУ.

Согласно стандарту превышение предельного значения температуры относительно средней температуры окружающего воздуха, равной 35° C, не должно превышать значений, указанных в таблице 1.

[Перевод Интент]

Тематики

• НКУ (шкафы, пульты,...)

EN

• temperature-rise inside assembly