We have two hydroelectric generators of 100 MW each. Unit 2 has more wear of carbon brushes on the slip ring than unit 1. Under the same operating conditions (load, field volts, field amps) the temperature of the slip ring of unit 2 is 25 C higher than unit 1. The brushes are of the same make and material. The only thing that is different about unit 2 is there is a minor oil leak from an oil reservoir above the slip rings. This oil reservoir is for the hydraulic oil (Tresso 46) supply to the runner blades of the Kaplan turbine.
In what way will a thin film of Tresso 46 between the slip ring face and the characteristics of the brushes etc?
What could be the cause(s) of the excessive carbon brush wear? I am confident that the brush springs are set to the appropriate tension.
In what way will a thin film of Tresso 46 between the slip ring face and the characteristics of the brushes etc?
What could be the cause(s) of the excessive carbon brush wear? I am confident that the brush springs are set to the appropriate tension.