answer: #Person1# introduces a new cleaning unit to #Person2# and explains it.
documents: #Person1#: Would you like me to show you our new cleaning unit? It's a clever design.
  #Person2#: Yes, I'd like to see that. What does it clean exactly?
  #Person1#: It washes the solvent off all the metal parts - the blades, trays etc. - and then sends it back into the system.
  #Person2#: What does the unit consist of?
  #Person1#: Well, it's basically two tanks, one for the dirty solvent and one for the clean solvent, a pump and a washing unit. Oh, and there's a cooling system and a filter. It's all controlled by a PLC system, that stands for Process Logic Control.