| Sažetak | Kako bi se ispitao kontaktni sistem potrebno je provesti mjerenje koje treba biti autonomno.
Za svako mjernje nužna je mjerna oprema što je u ovom slučaju DC izvor, multipleksor i
računalo sa odgovarajućim software-om. Predmet ispitivanja se postavlja u komoru zajedno
sa termoparovima. Termopar se spaja na karticu multipleksera u pripadajući kanal. Na
temelju toga multiplekser može prikupljati podatke o temperaturi, struji i vremenu ovisno o
tome kako mu je podešen sample rate ili vrijeme uzorkovanja. Programska logika mora
osigurati sljedivost i propagaciju informacija ili zadaća nizvodno bez nepotrebnih
ponavljanja akcija. Iz toga razloga, pokazano je programskom podrškom kako je moguće
vješto kombinirati princip Producer-Consumer i princip Simple State Machine. Consumer
obavlja zadatke koje pročita iz reda pomoću Read from queue elementa, dok ih unutar petlje
Enqueue element skida da bi se obavio zadatak, usvajajući ih pritom kao svoja stanja unutar
Case strukture i postoje: Init, Start, Measure,Evaluate,Idle, PS OFF, TempRise i Derating,
Exit. Uspješnom inicijalizacijom instrumenata i upuštanjem struje započinje mjerenje gdje
se spremaju podaci o temperaturnim promjenama i vremenu kad se to dogodilo u polja čime
se dalje ti podaci šalju u stanje obrade ili Evaulate. Tek kada je zadovoljen uvjet
temperaturne stabilizacije moguće je crtati potrebne krivulje. Radi preciznosti prilikom
obrade rezultata uzima se pet točaka (zabilježe se podaci o temperaturi i struji) koje su
sigurno u području temperaturne stabilizacije. Na osnovu toga izračuna se prosječni
derating factor, a uz zadani korak iteracije 0,5 A konstruira se temperature-rise i sličnim
matematičkim manipulacijama Dearting krivulja. Mjerenje je validno ukoliko nema
oscilacija otpora uslijed loše pripravljenog krimpa, termoparovi nisu prestari ili pogrešno
zalemljeni prema polaritetu ili tvistani u jednoj točci, uvjeti koji vladaju unutar komore nisu
narušeni i sl. Sukladno rezultatima mjerenja konstruktor kontaktnog sistema objektivno
procjenjuje kvalitetu i performanse proizvoda koji mora biti u kućištu da bi bio potpuno
funkcionalan i dakako komercijalno dostupan. |
| Sažetak (engleski) | In order to test the contact system it is necessary to perform a measurement that should be
autonomous. For each measurement, measuring equipment is necessary, which in this case
is a DC source, multiplexer and a computer with the appropriate software. The test object is
placed in the chamber together with the thermocouples. The thermocouple is connected to
the multiplexer card in the corresponding channel. Based on this, the multiplexer can collect
temperature, current and time data depending on how its sample rate or sampling time is set.
Program logic must ensure traceability and propagation of information or tasks downstream
without unnecessary repetition of actions. For this reason, the software has shown how it is
possible to skillfully combine the Producer-Consumer principle and the Simple State
Machine principle. Consumer performs tasks that it reads from the queue using the Read
from queue element, while within the loop the Enqueue element removes them to complete
the task, adopting them as its states within the Case structure and there are: Init, Start,
Measure, Evaluate, Idle, PS OFF , TempRise and Derating, Exit. By successfully initializing
the instruments and turning on the current, the measurement begins where the data on
temperature changes and the time when it happened are stored in the fields, which further
sends this data to the state of processing or Evaulate. Only when the temperature stabilization
condition is met is it possible to draw the necessary curves. For the sake of precision when
processing the results, five points are taken (data on temperature and current are recorded)
which are safe in the area of temperature stabilization. Based on this, the average derating
factor is calculated, and with a given iteration step of 0.5 A, temperature-rise and similar
mathematical manipulations of Dearting curves are constructed. The measurement is valid
if there are no resistance oscillations due to poorly prepared crimp, thermocouples are not
too old or incorrectly soldered to the polarity or twisted at one point, the conditions
prevailing inside the chamber are not violated, etc. In accordance with the measurement
results, the contact system designer objectively assesses the quality and performance of the
product that must be in the housing in order to be fully functional and, of course,
commercially available.
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