It usually begins innocuously: first a numb feeling in the thumbs, index and middle fingers during the night. But then later, pain and sensory disorders throughout the day too. The hand becomes less sensitive, the fine motor skills start to dwindle and the hand gets weaker.
Day-to-day tasks become increasingly difficult and certain professional activities are difficult or even impossible to accomplish. This is caused by what is known as carpal tunnel syndrome. A nerve in the hand is permanently trapped against a constricted area that is inflamed.
One suspected cause of this widespread condition is one-sided strain, which is often encountered in the electrical trade for example. There is a good case here for taking measures to guard against such conditions and prevent expensive employee absences. Choosing the right tool can help.
One of the most commonly recurring tasks in switch cabinet construction is the crimping of cables. This task is usually carried out using mechanical tools and in most cases, is completed without any problem at all. It can be become critical, however, when it has to be carried out by employees on a recurring basis. With a manual force of up to 20 kilograms per crimp, excessive strain in the wrist and forearm can occur over time.
One key factor is considered to be the number of crimp operations that are carried out on a regular basis. While a young and healthy employee who has not previously experienced excessive strain can easily achieve 100 to 150 crimps per day without their health being affected, the use of a tool with motorised drive is recommended for higher numbers of crimps.
Leading manufacturers now recommend tools that allow work to be carried out much more comfortably with far less physical strain. The electromechanical crimping tool Klauke micro® with 10.8 V lithium-ion battery, for example, requires a manual force of just two kilograms per crimp.
In other words: the force that needs to come from the hand and forearm is around 90 percent less than that required for a tool operated purely by hand. “When we developed our electromechanical micro, the aim was a crimping tool that is easy to use and would allow ergonomic and health-promoting work, thereby combining the benefits of a manual crimping tool with the ease of a cordless one in a single device”, explains Lutz Remmel, Product Manager at Klauke.
To make the day-to-day tasks of a qualified electrician easier and benefit from the timesaving, the selected tool should cover the broadest range of tasks possible. The electromechanical tool from the aforementioned manufacturer, for example, is able to process cable cross-sections from 0.14 to 50 square millimetres with a crimping force of up to 15 KN, with a long-term time saving compared to the mechanical crimping tool.
Because, in terms of the system concept, the tool is designed to take the interchangeable dies from Klauke’s 50 series, it is also suitable for crimping various cable types, cable end-sleeves, and also tubular cable lugs, insulated solderless terminals and pin cable lugs. This not only makes the tool a versatile companion for switch cabinet construction, it is also gentle on the joints and allows consistently fast operations for numerous other manual and industrial applications.
The sequence is always the same: first, the manual pre-clamping. When the operating lever is actuated, the crimping jaws close in order to fix the connectors. During this particular step, the material can be precisely aligned and positioned.
In the second step, the crimp is achieved by the force of the motor. The operating lever simply needs to be depressed fully and the tool automatically starts the crimping process, which takes no more than 1.5 seconds, depending on the material.
Once the crimp has been made, the operating lever is released to initiate the return movement, also fully-automatic, into the original position.
Electromechanical crimping tools reduce the physical effort, and offer the following advantages too: they not only achieve the best crimping results for minimum force, they also guarantee the consistently high quality of these results for years afterwards. This is because a suitable tool in faultless condition is crucial to avoiding under-crimps and over-crimps. Otherwise, the consequences can be hazardous: incorrectly-made crimps can, for example, increase joint resistance which can in turn cause temperature rises and ultimately cable fires. When choosing a tool, simple and reliable operability is the key to ensuring safety.
Profitability, of course, is the question posed by any investment. The cost of a branded electromechanical crimping tool is around 180 euro, or more for a manual crimping tool. Any concerns about the durability and reliability of the electrical variant are unfounded. For its micro model, for example, Klauke states a long service life if the service intervals are maintained (at 35,000 press cycles). The tool is equipped with a multi-function LED for maintenance display and data transfer, which can also be used to transfer crimp and tool data to a PC via a USB adapter from the accessories range. Test reports showing date and time can readily be created as a PDF for recording completed crimp operations. An effective way of demonstrating a safe and correct working method. Purely mechanical manual crimping tools do not offer this option of displaying wear and creating documentation.
And also the lithium-ion batteries now used in most tools give no cause for concern. These energy sources conform to a perfected technical standard that applies today in practically all sectors in which rechargeable batteries are used. Lithium-ion batteries are set apart by short charging times without memory effect and a constant, uniform power output. The charging time for the battery installed in the Klauke tool is around 40 minutes. A fully-charged battery, can then achieve some 300 crimps on copper cables with a cross-section of ten square millimetres in accordance with DIN 46234. Despite this high efficiency, the total weight of the tool, including the battery, is just 960 grammes.
Yet a far more important factor for assessing profitability, is sustaining the employee’s physical strength. The cost of sick leave due to carpal tunnel syndrome, which is mentioned at the beginning, tendinitis or tennis elbow, far outweigh those of procuring an electromechanical tool.
The decision to invest in an electromechanical crimping tool should be made according to economic calculations. For specialist operations in which large numbers of connections have to be processed quickly, purchasing such tools makes perfect sense. Electro mechanical crimping not only increases the efficiency of work processes, it also protects the health of employees. And since maintaining good health also means sustaining physical strength, such an added investment can benefit employer and employee in equal measures. Especially in light of demographic change and the shortage of specialists this brings about, physical fitness has become an economically valuable asset which must be sustained for as long as possible.