The HKS 3-1 and KS 3 tricot knitting machines can alternately process elastic and inelastic yarns by using a yarn tension control device. The system consists of a tubular tension bar carrier, yarn combs, profiled guides, and presser or tension springs mounted on hinged baseplates at the tension bar supports. The tension bar adjusts easily to work with inelastic yarns, such as nylon or polyester. Raising the holders and the tube to the stopper and tightening the screws makes space to insert the inelastic warp into the lowered tubular tension bar carrier with yarn combs. The tension bar carrier is then raised to the stopper into its working position. For elastane yarns, the tension springs are removed, the warp is inserted into the yarn combs in the lower position, and the holders and the tube are lowered against the stop pin into the working position.