The TorqueVario-S VDE screwdriver, available from Schneider Electric, is an individually calibrated precision tool for the professional installer, and one that is 17th Edition Wiring Regulation 134.1.1 compliant:

Electrical connections that are too loose can cause arcing and overheating, whereas over tightening does not improve reliability but can cause the bolt or screw to cut through the wire and also damage the connection (or even cause early screw failure). It can even break conductor strands. So over-torqueing and under-torqueing - such as invariably happens to some extent when tightening is done by hand - are both potentially risky. The answer is to use a torque screwdriver.
The TorqueVario-S VDE torque screwdriver available from Schneider Electric has been designed for the controlled tightening of the screw while providing user safety for electrical applications. Each coded kit comes with a matching factory calibration certificate providing peace of mind for the installer.
Get it right first time!
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