Concept:
In modern sizing machines such as Indiquip systems, the machine operates in defined production cycles called set lengths. After completion of each set, certain parameters must be reset to ensure consistency in the next run and to maintain process control.
Resetting ensures that machine settings such as tension control, speed coordination, and yarn feed parameters are restored to standard operating conditions.
Step 1: Understand set length concept.
Sizing is performed in batches called set lengths.
\[
\text{One set length} \Rightarrow \text{One controlled production cycle}
\]
Step 2: Identify machine requirement.
After each cycle:
• Process parameters may drift
• Synchronization must be restored
Hence reset is necessary.
Step 3: Evaluate options.
• Tension adjustment → continuous control, not reset requirement
• Cleaning → maintenance, not mandatory after each set
• Oil bath → irrelevant
Step 4: Final answer selection.
Thus,
\[
\boxed{\text{Reset after each set length}}
\]
Therefore,
\[
\boxed{\text{Option (B) is correct.}}
\]