Results 1 to 1 of 1

Helpful tips for testing Siemens SB-EC trip units (SBS circuit breakers)

  1. SecondGen's Avatar
    SecondGen is offline
    I push buttons.
    NETA Level III
    Join Date
    Jan 2014
    United States

    Helpful tips for testing Siemens SB-EC trip units (SBS circuit breakers)

    Name:  siemens-sbs-circuit-breaker.PNG
Views: 184
Size:  258.2 KB

    Siemens SBS circuit breakers come equipped with many different styles of trip unit, each utilizing a different means of supply power. The Sentron Energy Communicating Trip Unit (SB-EC) is the high-end microprocessor model which requires the SBEPS external power supply in order to activate the communications function and display screen.

    Name:  Untitled2.png
Views: 119
Size:  234.6 KB

    You can secondary injection test using the TS31 test kit without the power supply but you wonít be able to interface with the trip unit (i.e. change settings, reset logs, etc.) during the test. Primary testing is the same story, the protective functions of the trip unit are powered by the CTís but without the power supply you canít change settings, nor can you defeat ground fault.

    Name:  wrong-type.jpg
Views: 119
Size:  29.8 KB
    The SBAPM power supply typically used with SB circuit breakers (shown above) will not work with this trip unit.

    How to power up the SB-EC trip unit without the SBEPS power supply

    You can power the trip unit using a simple 5VDC and 12VDC source. Wires should be located on the right side of the breaker. In this example we are working with a SBS1212.

    Click image for larger version. 

Name:	wiring-diagram-1.png 
Views:	9 
Size:	33.0 KB 
ID:	175

    +5V to RT1 (+5V Red)
    -12V to RT3 (-12V Green)
    GND to RT4 (COM Black)
    +12V to RT2 (+12V White)
    (PDF wiring diagram is attached to this post)

    How to tell which SB Energy-Comm trip unit model you have

    SBxxTP01 - Basic protection and power measurement
    SBxxTP01G - Basic plus ground fault protection
    SBxxTP02 - Advanced protection, power measurement and harmonics
    SBxxTP02G - Advanced plus ground fault protection
    Reply to Post • 
    Attached Files Attached Files

Login or register to leave a reply!

Related Topics

  1. Video instructions for URC AC-PRO trip units
    By AlexT90 in forum Electrical Testing Talk
    Replies: 0
    Last Post: November 28, 2016, 01:36 PM
  2. Amprobe DM-III -- Helpful tips for downloading data from PQ mode
    By SecondGen in forum Electrical Testing Talk
    Replies: 3
    Last Post: January 11, 2016, 02:12 PM
  3. Tips for Westinghouse DH breakers that trip free or wonít close
    By SecondGen in forum Electrical Testing Talk
    Replies: 0
    Last Post: May 10, 2015, 09:12 AM

Related Content

Tags for this Thread

Search TestGuy
   Tag Cloud   Advanced Search
Follow us

Explore TestGuy

NETA Certification Training

Help and Support