Abstract: The drainage device includes a drainage chamber (9) which communicates via an inlet pipe (20) with a compressed air tank and is provided with an outlet orifice (16), elements (5,24) for closing the outlet orifice and elements (5,19,1,21) for opening the outlet orifice while partially closing off the inlet pipe. Application to gas-blast circuit breaker installations.

Abstract: A stabilizer (1) includes a first passage (20-23) which connects a compressed gas source (2-3) to the circuit breaker and a second passage (9, 16, 34, 22) which makes the circuit breaker communicate with the atmosphere, these passages being normally closed, as well as means (10) for opening the first passage when the gas pressure in the circuit breaker is lower than a first value and means (31, 13) for opening the second passage when the gas pressure in the circuit breaker is higher than a second value. Application to high-tension air blast circuit breaker.