Sagging Calculator
The length of the crop wire for various bed sizes
The weight of the crop places a burden on the crop wire, which means that the crop wire cannot run horizontally. There is a “sag” in the wire. The correct sagging of the crop wires is extremely important.
The length of the crop wire is determined by:
- The bed size
- The sag per bed
- The number of beds
- The end fastening
The actual length of the crop wire per bed when assembling is shown in the following table. The capital letters are explained by the drawing.
Calculation example:
Bed size: 5 metres
Bed quantity: 40
Crop wire sag: 200 mm
The end fastening
The number of metres of crop wire is then: 40 beds x 5021.31 mm crop wire/bed = 1 x 500 mm for the end fastening = 201352 mm or 201.5 metres.
Checking the correct sag
The sag of the wire means that extra wire is required for each bed. This length can be calculated with the sagging calculator. The extra length in one row can be checked by pulling the wire down in one bed (always pull the wire down in the middle). The distance that you have to pull the wire down is the ‘height difference of the wire for one bed’, indicated with ‘H’. This is shown in the diagram above.
Example values:
You have a row with 57 beds, each 5 metres long. The desired sag is 20 cm:
Input values
Bed size (A) = 5000 mm
Bed quantity (V) = 57 beds
Sag (C) = 200mm
Wire length per bed (D) = 5021.31 mm (use sagging calculator)
Height difference in 1 bed (H) must then be:
1845 mm