What to do When Your Tension Reading is Not Steady

When your tension reading is not steady, we often recommend switching the controller into manual mode to help diagnose the problem. If in manual mode and the tension reading is steady, contact a Montalvo Applications Specialist. It may just be simply that the controller is not tuned properly and there just needs to be a minor adjustment. If in manual mode and the tension is still not reading steady this indicates either a mechanical issue with the machine, or a problem with the load cells.BWC-web

1. The tension is actually stable (no variations at all) but the load cells are indicating that there is a variation.

a. This would usually indicate that either the load cell is not mounted securely to the machine frame, that the clamps holding the shaft are not tight, that the bearing in the roller is bad, or that there is a faulty electrical connection in the cable. First check your load cell installation for any of these issues.

2. If it is evident that the web tension is indeed fluctuating, then the load cells are operating correctly. This can only mean there is some sort of a mechanical issue with the machine or even the material itself. These can be (some noted below):

a. Roll of material not perfectly concentric. This can usually be seen if you watch the roll very closely. Another way to tell is, with no air on the brake; rotate the roll manually stopping it frequently. If you stop the roll and it continues to rotate by itself, then it is not concentric. A perfectly concentric roll should be able to be stopped anywhere.

b. If the shaft holding the roll is held by safety chucks – If you once again rotate the roll and you feel it bump every ¼ or half a turn, this indicates that the chuck or the shaft end is worn. This is very common.

c. Make sure that the brake modules are centered between the brake discs. If one of them is dragging on the disc when no air pressure is applied, readjust it.

d. If the material is very stretchable, the variation can be caused by this. If there is a number of rollers that the material passes over, and if they are all not turning freely or if the material is slipping or not turning a roller, this could also be an issue.

If you have any questions or require further assistance contact a Montalvo Applications Specialist.