What is the fine-grained topic of the following text: If the operator feels this is too slow or too fast, he may, by changing two resistors, increase recovery to as fast as 2 1/4 seconds for 2/3 level, ond 10 seconds for 90% level; or as slow as 11 1/4 seconds for 2/3 level, and 45 seconds for 90% level. Only return the topic.
Adjusting recovery speed in a system through resistor modification.