Installation (overvoltage) Category 
This product is powered by mains conforming to installation (overvoltage) category II. 
 
 
WARNING  
Make sure that no overvoltage (such as that caused by thunderbolt) can reach the 
product, or else the operator might expose to danger of electric shock. 
 
Installation (overvoltage) Category Definitions 
Installation (overvoltage) category I refers to signal level which is applicable to equipment 
measurement terminals connected to the source circuit. In these terminals, precautions are done 
to limit the transient voltage to the corresponding low level. 
Installation (overvoltage) category II refers to the local power distribution level which is applicable 
to equipment connected to the AC line (AC power). 
Pollution Degree 
Degree 2 
Pollution Degree Definitions 
Pollution degree 1: No pollution or only dry, non-conductive pollution occurs. The pollution has no 
influence. For example: a clean room or air-conditioned office environment. 
Pollution degree 2: Normally only dry, non-conductive pollution occurs. Occasionally a temporary 
conductivity caused by condensation may occur. For example: general indoor environment. 
Pollution degree 3: Conductive pollution occurs, or dry, non-conductive pollution occurs which 
becomes conductive due to condensation which is expected. For example: Sheltered outdoor 
environment. 
Pollution degree 4: Pollution that generates persistent conductivity through conductive dust, rain, 
or snow. For example: outdoor locations. 
Safety Class 
Class 1 – Grounded Product