Blower, Elapsed Time Meter, and AC Interlock.
applied to the blower. One
of this ac input is used to operate
elapsed time meter M1. Pins D and E of the ac input connector are
jumpered to permit external interlock wiring.
Thermal switch S1 is mounted on the heat sink of each power supply.
If a power supply overheats, the corresponding thermal switch closes.
The resulting path to ground causes a warning indicator on the system
indicator panel to light.