Instructions
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2. Explanation of symbols
  The symbol with the lightning in the triangle indicates that there is a risk to your health, e.g. due to an 
electric shock.
  The lightning symbol in the square permits current measurements on uninsulated, hazardous active con-
ductors and warns of the possible hazards. Personal protective equipment must be used.
  This symbol is used to highlight important information in these operating instructions. Always read this 
information carefully.
  This symbol indicates special information and advice on how to use the product.
  This product has been CE tested and complies with the necessary European guidelines.
  Protection class 2 (double or reinforced insulation, protective insulation)
IP54  Dust- and splash-proof.
CAT I  Measurement Category I: For measuring circuits of electrical and electronic equipment that is not directly 
supplied with a mains voltage (e.g. battery-operated devices, safety extra-low voltage systems, and signal/
control voltages). In the future, this category will be renamed CAT 0 or 0.
CAT II  Measurement Category II: For measuring electrical and electronic devices that are directly supplied with a 
mains voltage via a mains plug. This category also includes all lower categories (e.g. CAT I for measuring 
signal and control voltages).
CAT III  Measurement Category III: For measuring circuits of installations in buildings (e.g. mains sockets or sub-
distributions). This category also includes all lower categories (e.g. CAT II for measuring electrical devices). 
Measuring in CAT III is only permitted with test prods that are covered with caps or that have a maximum 
exposed contact length of 4 mm.
CAT IV  Measurement Category IV: For measuring at the origin of a low-voltage installation (e.g. mains distribution, 
electricity provider’s transfer points to homes) and outdoors (e.g. when conducting tasks on underground 
cables or overhead lines). This category also includes all smaller categories. Measuring in CAT IV is only 
permitted with test prods that are covered with caps or that have a maximum exposed contact length of  
4 mm.
  Earth potential










