The Functional Devices Model PSB40AB10, PSB100AB10, PSC40AB10, and PSC100AB10 24VAC Class 2 power sources are pre-packaged in a metal enclosure. These are used in temperature control systems, industrial applications and building automation systems, BAS. The panel-mount versions, PSB40AB10 and PSB100AB10, are available without the metal enclosure. These power supply units are available with either 40VA or 100VA power ratings. All models accept 120 volt AC input. The combination on/off switch and circuit breaker controls the output and a second on/off switch and breaker combination controls the incoming 120 volt AC power. Other features include a 120 volt AC convenience outlet, terminal strip wiring and LED indication of the output.