Hermetically-sealed transformers for electrosubmersible pump supply (TMGPN) with the voltage of 3kV are intended for electrosubmersible pump supply from alterating current mains with the voltage **0 V and frequency *0 Hz. Transformers TMGPN are manufactured with cover protected a person from touching to transformer live parts. Transformers are connected from high-voltage and low-voltage sides by means of cables. Transformers are intended for operation in regions with temperate and cold-temperate climate in the open air (State Standard Specification *******9). Operational conditions are: - environment is nonexplosive without any current-conducting dust; - height of installation above sea level is no more than ***0 meters; - mode of operation is continuous; - ambient temperature is from **5˚C to **0˚C for temperate climate; - ambient temperature is from **0˚C to **0˚C for cold-temperate climate; - transformers are not intended for operation in the conditions of shaking, vibration and snatching and in reactive environment. Symbolic representation of transformer types: Here is an example of symbolic representation of hermetically sealed transformer with the power of **0 kVA, with the high voltage of 3 kV and low voltage 0, *8 kV, nominal power HV ***8 V, winding connection scheme and group Yn/Yn*0, operational temperature is from **5˚C to **0˚C in terms of its order and in documentation of another item – “Transformer TMGPN***0/*-operational temperature is from **5˚C to **0˚C ; ***8/**0; Yn/Yn*0; TU *********************3”. Our transformers meet all the requirements of Russian Federation national standards and IEC standards that are proved by certification centre of OJSC Research centre of High-Voltage Gear (Moscow). Annually our production goes through inspection checkup by certification centre.