Do electronic trip circuit breakers like the Siemens SENSITRIP™ and the SB breakers come pre-set from the factory for a particular application?
The electronic trip units on the Siemens circuit breakers are not set for particular applications, but they are shipped with the trip adjustments set at the minimum positions. Due to the wide variety of systems and loads it is impossible for Siemens to pre-set circuit breakers for a specific application. Ideally a Coordination Study should be conducted for the specific system requirements and would list the needed settings for all of the over current protective devices in the system. If a coordination study has not been performed, a knowledgeable user with Siemens Time Current Curve software can determine the basic settings for the breakers. This software is easy to use and provides the tools needed to select settings, to determine coordination between breakers at each level in the system, and to provide a printout of the time current curve and a list of settings. This software is available free of charge from Siemens web site. To access this site, click on the link Siemens Time Curren
