Technical data
“Universal” spare circuit breaker 
The physical configuration and interlock 
logic allow the use of a single circuit 
breaker to serve as a “universal” spare 
circuit breaker at an installation site. The 
interlock logic checks the principal rating 
characteristics (continuous current, 
maximum voltage and interrupting 
current) and allows a circuit breaker to be 
inserted in any circuit breaker cell, 
provided that the ratings of circuit 
breaker equal or exceed the ratings 
required by the cell.
Single source responsibility
Single source responsibility is assured 
since the complete equipment is 
designed by Siemens and is 
manufactured and tested in a single 
facility. The vacuum circuit breakers  
are checked in the switchgear cells as 
part of production testing. After tests  
and interchangeability checks, the circuit 
breakers are separately packed for 
shipment.
Full ANSI design background
Full design integrity is assured. ANSl/IEEE 
C37.09 and C37.20.2 require design tests 
on circuit breakers and structures 
together. The type 3AH3 operator is 
produced in our global center of 
competence for circuit breakers in Berlin, 
and final assembly of both the drawout 
type 38-3AH3 circuit breaker and the 
switchgear structures occurs in a single 
facility. Siemens controls the entire 
process, from design concept to 
production. Records are maintained to 
and production is certified to ISO 9001 
requirements to document compliance 
with ANSl/IEEE standards.
UL or C-UL Listing available (40 kA 
only)
Where the arrangement of components 
allows, UL or C-UL Listing is available.
Quality systems
Facilities involved with application, 
engineering, design and production are 
certified to ISO 9001 requirements.
5
Overview










