Coil length
📏 How to find out the length of the cable without unwinding the coil?
The tool solves the main problem of warehouse accounting and installation: it determines the remaining wire on a drum or in a coil. The calculation is made using the geometric method - through the winding volume.
📝 What dimensions need to be taken?
For accurate calculations, arm yourself with a tape measure and calipers:
- D (Outer Diameter):The full diameter of the reel with the cable wound.
- d (Internal diameter): the diameter of the drum neck (or internal void if the cable is without a reel).
- h (Width/Height):winding width (distance between the drum cheeks).
- Ø (cable diameter): the thickness of the wire itself (it is better to measure with a caliper).
Where is this calculation applied?
🏗 Warehouse inventory: Allows you to count kilometers of cable products in minutes without the use of rewinders.
⚡ Checking residues on site: Before starting installation, make sure that the started bay has enough wire for a long route to avoid soldering in the middle of the line.
🚛 Acceptance of goods: Quick check of the supplier - whether the visual volume of the bay corresponds to the stated footage in the invoice.
If you need to calculate other parameters of the electrical network, for example, cross-section or voltage drop, go to the general section of all construction calculators.
Frequently asked questions (FAQ)
🔹 How accurate is this calculation?
The error is usually 5-10%. This is due to the “fill factor” - the cable never fits perfectly tightly, there is air between the turns. The calculator uses the average factor for factory winding.
🔹 Is it possible to count a flat cable (VVG-P)?
This algorithm is for round cable. For a flat wire, the error will be higher, since it fits into the coil differently. In this case, we recommend using the arithmetic average between the cable width and thickness in the “Diameter” field.
🔹 How to count a coil without a drum (in a skein)?
The principle is the same. In the “Inner diameter” field, enter the size of the empty space in the center of the skein, and measure the “Outer diameter” and “Height” according to the fact.