| 60 / | HD | POWER PLANTS |
| 643 | DF | MOTIVE FLUID ENERGIZED BY EXTERNALLY APPLIED HEAT {11} |
| 670 | DF | .~ Power system involving change of state {6} |
| 677 | ![]() | .~.~ Serially connected motor with intermotor supply or withdrawal of motive fluid {1} |
| 678 | DF | .~.~.~> Withdrawn fluid heats boiler feed indirectly |