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WEG Molded Case Circuit Breakers - User’s Manual
2
WARNING
Do not attempt to install or perform maintenance on equipment while it is
energized. Death, severe personal injury or substantial property damage
can result from contact with energized equipment. Always verify that no
voltage is present before proceeding with the task, and always follow
generally accepted safe ty procedures.
WEG is not liable for the misap plication or misinstallation of its products.
The user is cautioned to observe all recommendations, warnings and cautions relating
to the safety of personnel and equipment as well as all general and local health and
safety laws, codes and procedures.
The recommendations and information contained herein are based on WEG
experience and judgment, but should not be considered to be all-inclusive or
covering every application or circumstance which may arise. If any questions arise,
contact WEG for further information or instructions.
1. INTRODUCTION
1.1. GENERAL INFORMATION
The UBW250 circuit breaker (Figure 1) types UBW250 are 600 V ac maximum
rated devices with inter changeable thermal-magnetic trip units rated
250 A maximum continuous current. Refer to Table 1 for all available trip unit
ratings. UBW250 circuit breakers are listed in accordance with Underwriters’
Laboratories, Inc. Standard UL 489 and satisfy the (P1) requirements of the
International Electrotechnical Commission Recommendations No. IEC 157-1
Model W circuit breakers satisfy the requirements of IEC 947-2. Molded case switches
are listed in accordance with UL 489.
