Fronius VR 4040, Operating Instructions Manual

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up at high wirefeed speeds, the wire buffer prevents the spool-mass from accelerating jerk -
ily, meaning that the wire is exposed to only moderate tensile forces. During welding start-
up, the tensile force of the wire is only increased (as a function of the wirefeed speed) as
far as is necessary in order to achieve timely acceleration of the wire spool.
Although the unreeling device has been optimally preconfigured for a wide range of differ -
ent wire spools, wirefeed speeds and welding wires before leaving the factory, it is possible
to “fine-tune” it where needed.
The following key parameters can be adjusted:
- braking force of the wire-spool brake
- braking system response
- working position
- limitation of wire tensile force in the acceleration phase
For a detailed explanation of how the braking system works, and of how to adjust it, please
see the sections headed “Functional principle” and “Adjusting the braking system”.