Chapter1 TakingMeasurements with the NI 5620
©NationalInstruments Corporation 1-3 NI5620 User Manual
Caution Do not operate the devicein an explosive atmosphere or where there may be
flammablegases or fumes. The device can only be operated at or below pollution degree 2,
asstated in Appendix A,Specifications. Pollution is foreign matter, solid, liquid, or gas that
may produce a reduction of dielectric strength or surfaceresistivity. The following is a
description of pollution degrees:
•Pollutiondegree 1: No pollution or only dry, non-conductive pollution
occurs.T he pollution has no influence.
•Pollution degree2 : Normally only non-conductivepollution occurs.
Occasionally,however, a temporary conductivity caused by
condensation must be expected.
•Pollution degree3 : Conductivepollution occurs, or dry,
non-conductivepollution occurs, whi ch becomes conductivedue to
condensation.
Caution Signal connections must be insulated for the maximum voltage for which the
deviceis rated. Do not exceed the maximum ratings for the device. Remove power from
signal lines before connection to or disconnection from the device.
Caution This devicecan only be operated at installation category I, as stated in
Appendix A, Specifications. The following is a description of installation categories:
•Installation categoryI V is for measurements performed at the source
ofthe low-voltage installation. Examples are electricity meters and
measurements on primary overcurrent protection devices and ripple
control units.
•Installationcategory III is for measurem ents performed in the building
installation. Examples are measurements on distributionboards,
circuit-breakers,wiring, includi ng cables, bus-bars,junction boxes,
switches, socket-outlets in the fixedinstallation, and equipm ent for
industrial use and some other equipment such as stationary motors
with permanent connection to the fixedinstallat ion.
•Installationcategory II is for measurements performed on circuits
directly connected to the lowvoltage installation. Examples are
measurements on household appliances, portable tools and similar
equipment.
•Installation category I is for measurements performed on circuits not
directlyconnected to MAINS. Examples are measurements on circuits
notderived from MAINS, and specially protected (internal)
MAINS-derivedcircuits.
Caution Clean the devicewith a soft non-metallic bru sh.The device must be completely
dry and freefrom contaminants before returning it to service.