Winegrowers Supplies - Vine training - trellis with moveable pairs of catch wires
The minimum number of wires is five (one main training wire with a wire strainer, and two pairs of moveable catch wires on chains). It's difficult to work with only those if you arch the fruiting canes (Pendlebogen) as the growth is at different heights.
I used an extra single fixed top wire (with a wire strainer) about 50 mm down from the top of the posts. Later I clipped the earliest strongest shoots to that (the quickest way is with a Max Tapener), giving good support to the growth and stopping it falling over sideways within the double wires.
The double catch wires are moved up and down, starting with the lowest pair about 200 mm above the main training wire. The second pair being about 200 mm above that.
You wait for the growth to be well above the first pair, but not so high that it is too far through the upper pair. Then the lower wires are lifted out of the hooks, then outwards and down and under to gather most of the shoots, then hooked back in the original position.
A few weeks later the same is done with the upper pair of wires.
Weeks later when the growth is just above the top wire, the lower pair of wires are raised to about 250 mm above the upper pair, gathering in the trailing shoots.
Later when the growth is high enough (ideally this is just before flowering starts) the growth is 'topped', cut so that it is about 250 mm above the single top wire; like topping a hedge.
Later, double wire clips (e.g. red plastic R#45) are used to clip the pairs of wires together, holding them about 25 mm apart.
It's best not to catch all the shoots, or the foliage will be too congested, making spraying penetration difficult and allowing more mildews to develop.
That's the ideal procedure !