Ci gaba da Ikkicin Kusurfiyar Dabbobi | Sabbin Kusurfiyar Dabbobi
Don samun yakin da insulator na karamin soro, wanda ya shafi cewa ba a faru karkashin insulator, har zuwa insulator ita zai yi aiki da tattaunawa na insulator.
Abin da na gaba a kan tattaunawa na insulator zan iya taimaka maka masu yadda ake amfani da karkashin insulator. Saboda haka, tattaunawa na insulator ta tabbatar da ma'adanar insulator, kuma tsari na karkashin insulator ta haɗa da ma'adanar insulator.
Sabon Karkashin Insulator
Akwai sabon karkashin insulator wadanda suka haifar da karkashin insulator a sistem na karamin soro. Bana da abin da za su shiga a nan:
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Karkashin Insulator
Insulator na porcelen suna da alama uku. Alama mai karfi, alama mai fiti, da alama mai cement. Saboda yanayin al'adu, waɗannan alama suka yi aiki da dama. Wannan yanayin al'adu na alama suka taimaka wajen karkashin insulator.
Alama Mai Jirgin Insulation
Idan alama mai jirgin insulator an buga a wani wurin, insulator zai da yawan aiki da shi.
Porosity a Alama Mai Jirgin Insulation
Idan insulator na porcelen an yi a matsayin adadin lere da take, zai kasance da shi, kuma zai haifar da shi a magana da soro, kuma zai haifar da karkashin insulator.
Glazing Da Ba Tattauna A Cikin Insulator Ba
Idan cikakken insulator na porcelen ba a tattauna, mutane zai iya haifar da shi. Wannan mutane tare da abubuwan dust suka yi aiki da shi, kuma zai haifar da karkashin insulator.
Flash Over Across Insulator
Idan flash over an faru, insulator zai da yawan aiki, kuma zai haifar da karkashin insulator.
Mechanical Stresses on Insulator
Idan insulator an faru a wani wurin, zai da yawan aiki, kuma zai haifar da karkashin insulator. Zan iya taimaka maka masu yadda ake amfani da tattaunawa na insulator don tabbatar da ma'adanar insulator.
Tattaunawa na Insulator
Daga cikin British Standard, insulator na karamin soro zai yi aiki da:
Tattaunawa na flashover
Tattaunawa na performance
Tattaunawa na routine
Zan iya taimaka maka masu yadda ake amfani da:
Tattaunawa na Flashover
Akawo uku na tattaunawa na flashover suka yi aiki a insulator:
Power Frequency Dry Flashover Test of Insulator
Yanzu insulator da za a tattauna zai a baka a hanyar da za a amfani da shi.
Sau da haka, terminals na variable power frequency voltage source zai a baka a electrodes na insulator.
An yi aiki da power frequency voltage kuma zai a yi aiki da shi har zuwa adadin da aka tabbata. Adadin da aka tabbata ba zai da flash over voltage.
Voltage na hakan zai a yi aiki har zuwa da minute, kuma zai a duba cewa ba a faru flash-over ko puncher ba.
Insulator zai iya yi aiki da adadin da aka tabbata a lokacin minute baya baya bayan da flash over ba.
Power Frequency Wet Flashover Test or Rain Test of Insulator
A nan insulator da za a tattauna zai a baka a hanyar da za a amfani da shi.
Sau da haka, terminals na variable power frequency voltage source zai a baka a electrodes na insulator.
An yi aiki da insulator da shi suka yi aiki da water at an angle of 45o in such a manner that its precipitation should not be more 5.08 mm per minute. The resistance of the water used for spraying must be between 9 kΩ 10 11 kΩ per cm3 at normal atmospheric pressure and temperature. In this way we create artificial raining condition.
Now the power frequency voltage is applied and gradually increased up to the specified value.
This voltage is maintained for either one minute or 30 second as specified and observe that there should not be any flash-over or puncher occurred. The insulator must be capable of sustaining the specified minimum power frequency voltage for specified period without flash over in the said wet condition.
Power Frequency Flash over Voltage test of Insulator
The insulator is kept in similar manner of previous test.
In this test the applied voltage is gradually increased in similar to that of previous tests.
But in that case the voltage when the surroundings air breaks down, is noted.
Impulse Frequency Flash over Voltage Test of Insulator
The overhead outdoor insulator must be capable of sustaining high voltage surges caused by lightning etc. So this must be tested against the high voltage surges.
The insulator is kept in similar manner of previous test.
Then several hundred thousands Hz very high impulse voltage generator is connected to the insulator.
Such a voltage is applied to the insulator and the spark over voltage is noted.
The ratio of this noted voltage to the voltage reading collected from power frequency flash over voltage test is known as impulse ratio of insulator.
This ratio should be approximately 1.4 for pin type insulator and 1.3 for suspension type insulators.
Performance Test of Insulator
Now we will discuss performance test of insulator one by one-
Temperature Cycle Test of Insulator
The insulator is first heated in water at 70oC for one hour.
Then this insulator immediately cooled in water at 7oC for another one hour.
This cycle is repeated for three times.
After completion of these three temperature cycles, the insulator is dried and the glazing of insulator is thoroughly observed.
After this test there should not be any damaged or deterioration in the glaze of the insulator surface.
Puncture Voltage Test of Insulator
The insulator is first suspended in an insulating oil.
Then voltage of 1.3 times of flash over voltage, is applied to the insulator.
A good insulator should not puncture under this condition.
Porosity Test of Insulator
The insulator is first broken into pieces.
Then These broken pieces of insulator are immersed in a 0.5 % alcohol solution of fuchsine dye under pressure of about 140.7 kg ⁄ cm2 for 24 hours.
After that the sample are removed and examine.
The presence of a slight porosity in the material is indicated by a deep penetration of the dye into it.
Mechanical Strength Test of Insulator
The insulator is applied by 2½ times the maximum working strength for about one minute.
The insulator must be capable of sustaining this much mechanical stress for one minute without any damage in it.
Routine Test of Insulator
Each of the insulator must undergo the following routine test before they are recommended for using at site.
Proof Load Test of Insulator
In proof load test of insulator, a load of 20% in excess of specified maximum working load is applied for about one minute to each of the insulator.
Corrosion Test of Insulator
In corrosion test of insulator,
The insulator with its galvanized or steel fittings is suspended into a copper sulfate solution for one minute.
Then the insulator is removed from the solution and wiped, cleaned.
