National Instruments NI 9401 - Hazardous Locations

NI 9401 Operating Instructions and Specifications | © National Instruments | 19
Measurement Category I is for measurements performed on
circuits not directly connected to the electrical distribution system
referred to as MAINS voltage. MAINS is a hazardous live electrical
supply system that powers equipment. This category is for
measurements of voltages from specially protected secondary
circuits. Such voltage measurements include signal levels, special
equipment, limited-energy parts of equipment, circuits powered by
regulated low-voltage sources, and electronics.
Caution Do not connect the NI 9401 to signals or use
for measurements within Measurement Categories II,
III, or IV.
Hazardous Locations
U.S. (UL) .......................................... Class I, Division 2,
Groups A, B, C, D, T4;
Class I, Zone 2,
AEx nC IIC T4
Canada (C-UL) ................................. Class I, Division 2,
Groups A, B, C, D, T4;
Class I, Zone 2,
Ex nC IIC T4
Europe (DEMKO) ............................ EEx nC IIC T4