User manual
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2. Explanation of symbols
  The symbol with the lightning in a triangle indicates that there is a risk to your health, e.g. due to an electric 
shock.
  The symbol with an exclamation mark in a triangle is used to highlight important information in these oper-
ating instructions. Always read this information carefully.
  The arrow symbol alerts the user to the presence of important tips and notes on using the device.
  This product has been CE tested and complies with the necessary national and European regulations.
  Protection class 2 (double or reinforced insulation, protective insulation)
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).
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 probes with a maximum free contact length of 4 mm or with 
cover caps over the test probes.
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 lower categories. Measuring in CAT IV is only 
permitted with measuring probes with a maximum free contact length of 4 mm or with cover caps over the 
measuring probes.
  Earth potential










