Detailed information on cable length measuring devices
Cable length measuring device PAN KLM 30R
- Measuring method: Resistance measurement (milli-ohmmeter)
- For single and multi-pole conductors up to 30 km in length
- Especially suitable for installation cables
- BOTH cable ends are required for measurement
(alternatively: contact 2 conductors of a cable at ONE end and connect these 2 conductors at the other end) - Use the rotary switch to set the conductor cross-section and press the button to select copper or aluminum.
- From measured Resistance value, set Cross section and elected material calculated the device the Cable length.
- The accuracy of the device from 1 – 2% refers to the measurement of the Resistance, not the length!
- The shorter and thicker the cable, the less accurate the measurement becomes, since the resistance values are very small and small changes, such as those caused by oxide layers or different positioning of the crocodile clips on the cable, have a larger percentage influence.
- When converting resistance to length, additional Deviations in measurement results of the actual length appear.
These are due to physical reasons and are therefore unavoidable: - Different conductors of the same cross-section can be of the same length different resistance values (Single, multi-strand, fine-stranded, compacted or thinned conductors; Aluminium or copper quality, different manufacturers etc.)
- Length specifications provided by cable manufacturers can deviate by up to 10% from the actual length! The length specified on the packaging is therefore not a reliable measure of the actual length. A reliable comparison value can only be determined mechanically.
- Ways to improve accuracy:
- To store the resistance values of frequently used cables, the device has 8 individual memory locations.
This allows you to measure the lengths of 8 different cables with greater accuracy. - Or you measure the resistance of a cable with known length and note this value.
Then measure the resistance of other cables of the same type and calculate from this the length this cable. - If the accuracy of the measurement is not satisfactory, please check all factors that may affect the measurement result:
- Are all the batteries in the measuring device in good condition? (The batteries supplied may be too weak when first used.)
- Do the meter and cable have the same temperature?
- Are the test cables free from damage that could change the resistance (e.g. broken strands due to kinks, oxidation due to moisture penetration, etc.)?
- Is the cable to be measured free from damage that could change the resistance (e.g. broken strands due to kinks, oxidation due to moisture penetration, etc.)?
- Did you calibrate the measuring device before starting the measurement (see operating instructions)?
- Are the cross-section and material (Cu or Al) set correctly?
- Are all 4 plugs of the test leads cleanly and firmly inserted?
- Are both crocodile clips firmly attached to the cable ends?
- Are both cable ends free of oxide layers, which can increase the contact resistance?
- Do you compare the measurement result with the actual mechanically measured length and not with the manufacturer's information on the packaging, which can deviate up to 10% from the actual length?
If you can answer all questions with "yes" and the measurement result still deviates more than 10% from the actual length, we can check your device.
A serious inspection is only possible if you send us both your device and the cables whose measured length has shown large deviations.
- For further information please see the Datasheet and in Application video.
Cable length measuring device PAN KLM-2000
- Measuring method: Signal reflection measurement (“echometer”)
- For multi-pole cables up to 2,000m (at least 2-pole)
- Especially suitable for network and coaxial cables (antenna cables)
- Only ONE cable end is required for measurement
- Conductor cross-section and material do not matter
- Before measuring the length, measure the VOP value of the cable.
(Velocity Of Propogation = speed of signal propagation in the conductor)
This requires a piece of cable of known length.
You can then save the cable on the device under any name you like.
You can then measure other lengths of the same cable. - The device is suitable for measuring the length of the following conductor types:
– Network cable (RJ45 connector)
– Coaxial cable (BNC connector)
– Any other multi-pole cable (contact via test probes or crocodile clips) - For further information please see the Datasheet and in Application video.
- The following applies to BOTH devices:
– It does not matter whether a cable is on a reel or has already been laid.
– The cable must be de-energized.
