Method for control of yarn processing equipment

A method for starting or stopping each of at least three rolls (26, 34, 42) arranged in at least two separately controllable roll-sets used for processing a yarn (Y) in a stretch-break process, each roll-set comprising at least two of the rolls, the stretch-break process including at least one jet consolidation device (32, 36, 52), the method comprising the steps of:

• a) for each roll-set, changing the speed of each roll from an initial condition to a steady state condition in coordination with a change in speed of at least one of the other rolls in accordance with a predetermined sequence, wherein the predetermined sequence is created by the steps of:
• i) selecting a candidate speed for each of the three rolls;
• ii) validating the candidate speed for each roll against predetermined operability criteria;
• and
• iii) for speeds that meet the operability criteria, setting the speed for each of the three rolls;
• and
• b) selecting at least one operating parameter for the jet, wherein the jet operating parameter comprises an operating pressure and wherein the operating pressure is selected as a continuous range of pressures,
• such that simultaneous complete breakage of a yarn (Y) being processed in a stretch-break process is minimized.