User's Manual

NI 9201/9221 with DSUB Isolation Voltages

Channel-to-channel........................... No isolation between

channels

Channel-to-earth ground

Continuous ................................. 60 VDC,

Measurement Category I

Withstand.................................... 1,000 V

rms

, verified by a 5 s

dielectric withstand test

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 9201/9221 with DSUB to

signals or use for measurements within Measurement

Categories II, III, or IV.