Issue 07/04  Safety Instructions 
MICROMASTER 420    Operating Instructions   
6SE6400-5AA00-0BP0 
7 
Safety Instructions 
The following Warnings, Cautions and Notes are provided for your safety and as a 
means of preventing damage to the product or components in the machines 
connected. This section lists Warnings, Cautions and Notes, which apply generally 
when handling MICROMASTER 420 Inverters, classified as General, Transport & 
Storage, Commissioning, Operation, Repair and Dismantling & Disposal. 
Specific Warnings, Cautions and Notes that apply to particular activities are 
listed at the beginning of the relevant chapters and are repeated or supplemented 
at critical points throughout these chapters. 
Please read the information carefully, since it is provided for your personal 
safety and will also help prolong the service life of your MICROMASTER 420 
Inverter and the equipment you connect to it. 
General 
 
WARNING 
♦  This equipment contains dangerous voltages and controls potentially 
dangerous rotating mechanical parts. Non-compliance with Warnings or 
failure to follow the instructions contained in this manual can result in loss of 
life, severe personal injury or serious damage to property. 
♦  Only suitable qualified personnel should work on this equipment, and only 
after becoming familiar with all safety notices, installation, operation and 
maintenance procedures contained in this manual. The successful and safe 
operation of this equipment is dependent upon its proper handling, 
installation, operation and maintenance. 
♦  Risk of electric shock. The DC link capacitors remain charged for five minutes 
after power has been removed. It is not permissible to open the 
equipment until 5 minutes after the power has been removed.  
♦  HP ratings are based on the Siemens 1LA motors and are given for 
guidance only, they do not necessarily comply with UL or NEMA HP 
ratings. 
 
 
CAUTION 
♦  Children and the general public must be prevented from accessing or 
approaching the equipment! 
♦  This equipment may only be used for the purpose specified by the 
manufacturer. Unauthorized modifications and the use of spare parts and 
accessories that are not sold or recommended by the manufacturer of the 
equipment can cause fires, electric shocks and injuries.