Installation with sealing device for a lamp

An installation, comprising:

• a lamp, a circuit for cooling said lamp, at least one electrical connection area of the lamp and at least one sealing device for sealing between said at least one electrical connection area of the lamp, external to said lamp, and the cooling circuit of said lamp, the lamp comprising a tube adapted to enclose a heat source and at least one electrode, adapted to generate said heat source, said at least one electrode being positioned at one end of the tube and connected to said connection area, said cooling circuit comprising a cooling chamber which surrounds said tube of the lamp and wherein a cooling fluid circulates with a cooling fluid pressure, said installation being wherein said at least one sealing device comprises an overpressure chamber positioned between said cooling chamber and said at least one electrical connection area, said at least one sealing device further comprising two seals which are spaced apart from each other by being positioned on either side of said overpressure chamber, at least one of said two seals defining a first sealing wall between the cooling chamber and the overpressure chamber, and the other seal defining a second sealing wall between the overpressure chamber and said at least one electrical connection area, said overpressure chamber comprising a pressurized overpressure fluid,
• the pressure of the overpressure fluid being higher than said pressure of the cooling fluid present in the cooling chamber.