The International Safety Standard IEC61010
This Safety Standard which is established for protecting operators and environment stipulates safety requirements for measuring instruments and electric equipment. The IEC standard defines the degree of pollution, measurement classification, barrier, material, spatial distance and creepage distance to assure safety. The impulse withstand voltage as transitional energy is estimated from the measurement category and main power supply voltage to conduct tests for measuring instruments.
Test voltage (impulse withstand voltage)
The output impedance of an impulse generator is 12Ω in the measurement category II, and 2Ω in measurement categories III and IV.
| Nominal AC or DC line of main power supply and neutral voltage |
CAT.II | CAT.III | CAT.IV |
| 300V | 2500V | 4000V | 6000V |
| 600V | 4000V | 6000V | 8000V |
| 1000V | 6000V | 8000V | 12000V |
