I have ordered a second relay array. I decided to order it because it will help facilitate a second stage cooling unit to be added without having to wait for it to arrive.
There are several aspects of the Freeze Dryer that needs to be controlled by relays.
The compressor needs to be cycled in order to keep it from overheating.
The compressor fan needs to be cycled independent of the compressor. If the compressor is off, the fan may still need to be on in order to continue removing heat from the condenser coil.
The fan in the trap needs to be cycled.
The fan in the chamber needs to be cycled
The compressor needs to be cycled
The second stage cooling system may not be needed, but if it is, it will need a relay.
