Development and introduction of the room sealed packaged engine alternator set

In the early 1980s British Telecom embarked upon a program to introduce small packaged automatic standby AC power plant at small rural telephone exchanges. This development extended the operational reserve from 24 hours to 10 days. The background to the design and development of a new room sealed engine alternator set using a balanced flue arrangement is described. The balanced flue unit is ventilated independently of the environment in which it is sited, so that it is no longer necessary to have separate power rooms. Cooling and aspiration air are drawn through louvers from outside the building, through an acoustic pod and into the acoustically treated engine alternator cubicle. The air is then circulated around the engine set and then deposited with the exhaust out through the same acoustic pod and louvers to atmosphere. Initially the sets are rated between 6 kVA and 20 kVA for single and three-phase applications.<>