Stripping cables is one of the most common tasks in electrical installations. The procedure is the same for almost all cables: cut and strip the sheath, fit the core with a ferrule or connect it to the circuit using a clamp - done! Provided you have the right tools, stripping and stripping is not rocket science and even inexperienced craftsmen can do it in no time at all.
Our guide explains what is important when stripping wires, what the 4-step method is all about and which tools are indispensable for cutting and stripping cables depending on the selected cable cross-section.
What does stripping mean?
Why do you actually strip cables? Without stripping, no electrical or signalling connection can be established between two wires or between a wire and a connected device. To strip cables, their insulating layer - generally referred to as the sheath - is removed using a knife or a suitable tool such as a wire stripper.
What is the difference between stripping and stripping?
In contrast to stripping, in which the insulating and non-conductive plastic layer is removed from individual strands or cores, the cables - e.g. a 5-core 2.5 mm² power cable - are stripped of their outer protective layer (the sheath) during stripping.
Tools for stripping cables
A common, but not necessarily safe and easy-to-use tool for stripping cables is a sharp cutter knife. Depending on how many metres need to be completely stripped, it is also advisable to purchase a cable stripping machine. Inexpensive, manually operated models are available for less than 100 euros.
Wire stripper
Stripping pliers are an indispensable tool for electricians. They can be adjusted to different cable cross-sections without damaging the conductors. Stripping pliers are used when the insulating protective layer needs to be removed from the wire ends so that they are electrically conductive.
Stripping cables with pliers is therefore probably the most common method for stripping live cables in the home or in fuse boxes and control cabinets in order to fit them with a cable clamp or wire end ferrule.
There are also pliers for stripping cables, the function of which is no different from that of cable stripping pliers. A special wire stripper is recommended for stripping thin cables, which can also strip wires with a cross-section of 0.4 mm cleanly and without damage.
Cable bending tools
Cable strippers are usually tubular, can be opened lengthways and have an internal blade. Universal strippers have a slider on the outside that can be used to adjust the cutting depth to the outer diameter of the cable to be stripped, e.g. 2.5 mm² or 4 mm².
Cable stripper - Cable stripping machine
A cable stripper or cable stripping machine is often used by recycling or recyclables dealers. The advantages of a machine that can strip cables include the fact that many metres of cable can be quickly stripped of their sheathing in a short space of time. Furthermore, a cable stripping machine can process different cable cross-sections. A machine designed for cable stripping has, for example, interchangeable perforated discs through which the cable is fed into the cable peeler.
Stripping cables without a machine is also possible with a radial cable cutter, which is also cheaper than a cable stripping machine.
Stripping cables without tools
As a general rule, cables
should always be stripped of their insulation using suitable pliers or a
stripper if possible. This minimises the risk of injury and the wires
in the cables are not damaged. However, with a little practice and
feeling, cables can also be stripped without tools.
The advantage: A cutter knife is available in almost every household and is sharp enough to penetrate the sheath of a 5-core 4 mm² cable.
Stripping knife
A stripping knife is preferably used when you want to strip thick cables. For example, if you want to strip a 16 mm² cable to connect to a battery, or if the available wire strippers are too small to strip a 25 mm² NYM cable.
Important for a wire stripping knife and side cutters: The cutting edges must always be sharp. When stripping the cable without pliers, it is also important to be able to cut the cable lengthwise with the stripping knife.
Tools for stripping cables
How do you strip a cable?
Stripping with a stripping knife can be divided into the following steps:
- Set the blade depth of the stripping pliers to the diameter of the cables in question. Then place the stripper on the cables and push the blade upwards using thumb pressure.
- Position the stripping blade at the desired point on the cable and release the push button to allow the blade to cut into the insulation.
- Rotate the knife once through 360 degrees around the cable to cut all the way round the sheath.
- Now pull the knife lengthwise along the cable to the end of the cable to completely remove the sheath.
- The bare stranded wire is now exposed and can either be connected to a device or a wire end ferrule can be attached and crimped, for example.
To remove the cable insulation, e.g. to strip the insulation from a power cable, special pliers are recommended, which can also be used to strip thin copper cables without damaging them. The professional stripping of insulation to connect devices and control cabinets with cables of different cross-sections is also often referred to as stripping wires.
Trainees in the field of electrical engineering or mechatronics are often taught how to strip cables using the 4-step method:
- Preparation
- Demonstrate and explain the process
- Copy and have it explained
- Practise the process and internalise the method
Stripping single-core cables
A thin stranded wire is best stripped with a precision wire stripper. Depending on the cross-section and properties of a cable, a conventional wire stripper can also be used to strip the insulation, e.g. a fine-core H07V-K cable.
Stripping and stripping multi-core cables / sheathed cables
To strip the insulation from a power cable with its robust and tough sheath, we recommend using a stripping tool with the right diameter. Even thick underground cables can be easily stripped in this way.
An overview of the right tools for stripping and stripping:
| Cable type / cable type | The right tool for stripping |
|---|---|
| Earth cable | Outer sheath cutter with replaceable blade, suitable for circumferential and longitudinal cutting, adjustable cutting depth up to the cable insulation |
| NYM cable | Cable knife to remove the PVC sheath, e.g. with a cable stripper, the insulation of the individual wires can then be cut to the appropriate length with stripping pliers, e.g. to fit them with cable clamps and feed them into a wall junction box. |
| CAT cables | A cable stripper in the appropriate size (adjustable) is suitable for stripping the network cable and removing the PVC sheath quickly and conveniently. If the individual wires are not crimped directly with a suitable and self-cutting RJ45 plug, the insulation can be removed using a precision wire stripper. |
| Rubber cable | A cable stripper of the appropriate size can also be used here. Important here: The internal blade should be as sharp as possible if you want to strip a H07RN-F rubber cable, for example, as the rubber is tough and can give way. |
| ÖlFLEX cables |
Ölflex Classic 110 cables, which are often used as connection and control cables, are very robust and, depending on the cable version, reinforced with glass fibre.
|
How do you properly strip antenna cable / coaxial cable?
It doesn't matter whether you want to strip single or double-shielded SAT cables: It is important that the wire braiding under the outer sheathing is not damaged. When stripping satellite cables, it is also important to ensure that the rigid inner conductor is only stripped to such an extent that it does not protrude too far out of the plug after unscrewing an F connector. In order to strip the SAT cables correctly, we recommend using a wire stripper and suitable stripping pliers. If you do not want to strip SAT or LNB cables using this method, you can also consider purchasing special crimping pliers, which can be used to easily crimp F connectors to the cables.
How can cables be stripped quickly?
In general, cables can be stripped of their insulation very quickly with a suitable wire stripper. A suitable tool is indispensable, especially in the field of electrical installation, where many cables have to be stripped with consistent quality and exact dimensions. This also applies if you need to remove the cable sheath. In this case, a sharp stripping tool is highly recommended.
Trick for stripping cables: If cables are to be delivered to the recycler stripped and there is no stripping machine available, a trick can help. To do this, a sharp knife is placed on the table and secured and the cable is pulled through underneath. Depending on the type of cable, it may also be sufficient to strip only part of the sheath and then pull in the opposite direction on the inner conductor and the sheath to separate them.
Trick for stripping cables: If no wire strippers are available, a rubber cable, for example, can also be stripped relatively quickly using side cutters. To do this, use the side cutter to apply pressure to the insulating layer around the cable without damaging the wire. Once the insulation material has been cut, pull the side cutter towards the end of the cable while applying slight pressure.
How far must wires be stripped?
Depending on the application, e.g. for branches for complex circuits, it may be necessary to strip the insulation from the centre of a cable. Stripping pliers can be used for this, which are used twice to strip the cables to the desired length.
How far the wires have to be stripped also depends on the terminal or ferrule that is used. A common length to which the cables for crimp sleeves must be stripped is 10 mm. If you have stripped a cable too long, you can use heat shrink tubing to re-insulate the copper strand that has been stripped too far.
Despite careful editing and checking of the content, Stecker Express assumes no liability for the topicality, correctness, completeness and quality of the information provided.
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