The failure or malfunction of many transformers or similar equipment can be directly attributed to the lack of proper control of the level of moisture entering the equipment. It is essential, therefore, that a very low level of humidity is maintained in the air space in the top of the conservator tank to avoid deterioration of the insulating properties of the cooling medium.
Transformer breathers provide an economic and efficient means of controling the level of moisture entering the conservator tank during the change in volume of the cooling medium and/or airspace caused by temperature changes. However, with a new moisture content specification of oil being kept at less than 35 ppm moisture (ASTM D-1533 test method), higher performance desiccant than silica gel is needed. ZEOZORB transformer breathers exceed the ASTM D-1533 testing specifications and out perform silica gel breathers by over 75% at average operating temperatures 77°F.
In addition, testing shows that if the free air volume above the conservator tank oil is kept very dry, below 100 PPM it will actually liberate and pull moisture from within the transforming insulating lubricant, maximizing performance and life. This dynamic is crucial to optimize operations and maintenance procedures.
High Voltage Enclosures – High voltage motor protection desiccators provide protection against corrosion, dampness, and contamination in electrical, high voltage motors and switch gear. These desiccators incorporate a humidity which monitors saturation and indicates when desiccant change or cartridge replacement is required. They are blue when the desiccant is dry and turn pink when the maximum amount of moisture has been adsorbed. For our full range of desiccators, please visit our Breather Desiccators page.
Switchgear SF6 – Drytech Inc. offer a range of desiccant solutions to combat the problems of moisture within SF6 filled high voltage switchgear enclosures. Sulphur hexafluoride (SF6) is used as an insulating gas in transmission and distribution equipment such as switchgear and circuit breakers.
In order to maintain SF6 insulation properties and to reduce the formation of unwanted secondary decomposition products the amount of water vapor in the gas insulated system (GIS) should be kept to a minimum.
If moisture levels are not kept to a minimum then the formation of acidic by-products, such as Hydrogen fluoride, Sulphur dioxide, Sulphur fluoride and thionyl fluoride can be generated. This reaction may yield hydrofluoric acid, which is extremely corrosive and will react with electrical equipment components.
In order to maintain these low levels of moisture, a passive desiccant solution must be included within the cabinet.
Drytech suggests that a large pore molecular sieve (13x) be used as this has the ability to co-adsorb both moisture and arcing by-products. See our range of Desiccant Bags for a solution.
Drytech Transformer breathers reduce the relative humidity levels in a consevator tank to less than 5% RH.
|Model||Desiccant Capacity||Connection||Transformer mVA||Transformer Oil Quantity||Height|
|R||1.32 lbs||¾” FNPT||< 1.25 mVa||400 gallons/1500 liters||6.2"|
|R1||2.64 lbs||¾” FNPT||3 mVa||800 gallons/3000 liters||10.2"|
|R2||4.2 lbs||¾” FNPT||6 mVa||1250 gallons/4750 liters||14.2"|
|Dim. "B"||14.76” (375mm)||21.85” (555mm)||28.94” (735mm)||19.09” (485mm)||25.39” (645mm)|
|Dia. "A"||10.03” (255mm) diameter||13.97” (355mm) diameter|
|Dim. "C"||‘V,W, & X’ uses 3/4” FNPT, ‘Y&Z’ uses 1” FNPT|
|Transformer Rating||9 mVA||30 mVA||60 mVA||100 mVA||180 mVA|
|Max Transformer Oil Quantity||11,350 liters||22,700 liters||34,050 liters||45,450 liters||68,150 liters|
|Desiccant weight||7.2 (10kg)||10.5 (4.75kg)||13.2 (6kg)||17.6 (8kg)||22 (10kg)|
|Unfilled weight||13.3 (6kg)||17.6 (8kg)||24.25 (11kg)||30.8 (14kg)||39.7 (18kg)|
Drytech Transformer Breathers operate as your first means of protection againt moisture contamination. Transformer breathers take the approach of filtering atmospheric air BEFORE it enters your equipment, rather than trying to take moisture out AFTER it has been introduced into a system.
|Series||ZEOZORB Transformer Breathers|
|Dim. “A”||15.75” (400mm)||17.32” (440mm)||22” (560mm)||26.77” (680mm)|
|Dia. “B”||8.46” (215mm) diameter|
|Dim. “C”||4.5” (115mm) 4 hole flange|
|Transformer Rating||10,000 kVA||15,000 kVA||20,000 kVA||25,000 kVA|
|Max Transformer Oil Quantity||10,782 liters||13,620 liters||18,159 liters||22,698 liters|
|Desiccant weight||10.5 (4.75kg)||13.2 (6kg)||17.6 (8kg)||22 (10kg)|
|Unfilled weight||17.6 (8kg)||24.25 (11kg)||30.8 (14kg)||39.7 (18kg)|