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  • Selection of carrier gas of gas chromatographic system Gas source is the place where the carrier gas and auxiliary gas comes from. Generally the carrier gases are hydrogen, nitrogen, helium, argon and air etc. The selction of carrier gas is based on requirements of detector, and also the effect of analytic method to analytic period, column efficiency and ...
  • How to replace voltage-boosting transformer of MG-II dielectric strength test se 1. Remove two white color high voltage columns in high voltage chamber. 2. Remove four screws at four-corner of the panel, then, slightly lift up the panel. 3. You will see there are four screws at four-corner of the baseplate, remove these four screws, replace the transformer. 4. Re-install the test ...
  • Quality Index System of Oil Good oil has a fixed quality index system (QQIN). It is measured by the ratiio of interfacial tension (IFT) to neutralization number (NN). Generally, for a good oil, QQIN is 1500. QQIN = IFT/NN
  • Interfacial Tension of Transformer Oil It is a process of measuring tension at the interface between transformer oil and water which do not mix. It is expressed in dyne/cm. It is a very sensitive test. Good oil will have an interfacial tension between 40 dyne/cm and 50 dyne/cm. Oil oxidation reduces the interfacial tension. If the interfacial ...
  • Acidity of Transformer Oil As time goes, the transformer oil becomes aged. Water, heat, oxygen, to acertain extent, accelerate ageing. Alcohol, organic acid, peroxide, ketone and some other gases are produced from oil decompostion. Acid comes from some external sources. Acidity level above 0.2mgKOH/g is not tolerable for normal ...
  • Dielectric Strength of Transformer Oil The dielectric strength of transformer oil is a measure of the oil's ability to withstand electrical stress without failure. Water, sediment and conducting particle reduce the dielectric strength of transformer oil. Combination of these tends to reduce the dielectric strength to a greater degree. Clean ...
  • Water Content in Oil Water is harmful in power equipment because it is attracted to the places of greatest electrical stress. Water accelerates the deterioration of both the insulating oil and the paper insulation, liberating more water in the process (heat catalyzed). This is a never ending circle and once the paper insulation ...
  • How to replace temperature sensor and main board of K620 gas sampler? 1. Remove screws at rear cover of vibrator and remove rear cover. 2. Remove screws around the baseplate of vibrator, slightly lift up shell, then, you can see the main board (the same as the one you received.). 3. Pull out the old temperature sensor, and plug in the newly received one, then connect to ...
  • Procedure of Transformer Oil Breakdown Voltage Test The procedure of transformer oil breakdown voltage test is given below: To assess the insulating property of transformer oil, a sample of the transformer oil is taken and its breakdown voltage is measured. • The transformer oil is filled in the vessel of the testing device. Two standard-compliant test ...
  • Power Supply of Gas Chromatography for Analyzing Transformer Oil Dissolved Gases AC 220V±10%, 50Hz±0.5 power supply with capacity of more than 2500VA is required, and the power source should not contain a strong noise. The ground wire of GC2010D should be connectedto the exclusive ground peg. The peg terminal should beconnected with copper net and buried into the wet soil by one ...