National Instruments NI 9401 - Manual (Page 16)

NI 9401 Operating Instructions and Specifications 16 ni.com
Safety
Maximum Voltage 1
Connect only voltages that are within the following limits.
Channel-to-COM .............................. ±30 V max on one channel
at a time, Measurement
Category I
Isolation Voltages
Channel-to-channel........................... None
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
1 The maximum voltage that can be applied or output between any channel and COM
without damaging the module or other devices.