Loading
Back to
View All
  • Products
    • ALL PRODUCTS
      • Contactors
      • Overload Protection
      • Starters + Enclosed Product
      • Motor Controllers + MCCBs
      • Softstarters
      • Circuit Protection
      • Disconnect Switches
      • Rotary Cam Switches
      • Control + Timing Relays
      • Pilot Devices
      • Signaling Devices
      • Terminals
      • Power Supplies
    • Custom Control Panels
      • Capabilities
      • Combination Starters
      • Explosion Proof
      • Multi-Speed and Reduced Voltage
  • Library
    • LIBRARY
      • Product Catalog
      • Literature
      • Cross Reference
      • Technical Tips & FAQs
      • CAD Drawings
      • Wiring Diagrams
    • APPROVALS
      • UL/CSA Documents
      • CE-DOC
      • Atex
      • CCC
      • RCM/TUV/ABS/RINA
      • ISO9001
      • SUVA Certificates
      • Functional Safety Data
      • Environmental Compliance
  • Company
    • COMPANY
      • About Sprecher + Schuh
      • Contact Us
      • Industries Served
      • Success Stories
      • Terms & Conditions
      • Privacy Policy
      • Technical Support
      • International
  • Sales
    • SALES
      • Find a Reseller or Sales Rep
      • Become a Distributor
      • B2B Portal
    • CONTACT US
      • United States
      • Canada
      • International
  • Support
    • SUPPORT
      • Technical Support
      • Technical Tips & FAQs
      • Find a Reseller or Sales Rep
      • Contact Us
      • B2B Portal
Tech Tips
    • Contactors
    • Contactors
    • Overload Protection
    • Overload Protection
    • Starters & Enclosed Products
    • Starters & Enclosed Products
    • Motor Controllers & MCCBs
    • Motor Controllers & MCCBs
    • Softstarters
    • Softstarters
    • Circuit Protection
    • Circuit Protection
    • Disconnect Switches
    • Disconnect Switches
    • Rotary Cam Switches
    • Rotary Cam Switches
    • Control Relays & Timers
    • Control Relays & Timers
    • Pilot Devices
    • Pilot Devices
    • Signaling Solutions
    • Signaling Solutions
    • Terminal Blocks
    • Terminal Blocks
    • Power Supplies
    • Power Supplies
    • Electrical Industry Codes
    • Electrical Industry Codes
 


L8 And L9 Trip Curves And Trip Times On DC Applications

 

Question:

  • Are there trip curves and documentation for trip times when using L8 UL1077 supplemental protectors or L9 circuit breakers in DC applications?

Answer:

When using these products on DC applications or DC loads, refer to the published trip curves and times for AC applications as show in the current catalog or the UL Application Guide. Use a factor of 1.5 for the magnetic instantaneous trip X the continuous current rating (In).

The thermal trip times remain the same for both AC and DC applications. Refer to the table to calculate trip times for DC applications.

 
L8 Supplemental Protectors Instantaneous Trip Times multiple for AC Current (I/In) becomes multiple for DC Current (I/In)
B Trip Curve 3 to 5 4.5 to 7.5
C Trip Curve 5 to 10 7.5 to 15
D Trip Curve 10 to 20 15 to 30
L9 Circuit Breaker Instantaneous Trip Times multiple for AC Current (I/In) becomes multiple for DC Current (I/In)
C Trip Curve 5 to 10 7.5 to 15
D Trip Curve 10 to 20 15 to 30

For additional information please contact your nearest authorized distributor, sales representative, or call our customer service or technical support lines.

Sprecher & Schuh Series L8 and L9 Circuit Protection groups

Related Links

Portable Document Format.pdf file type L8/L9 UL Application Guide

Follow us

  • Facebook logo
  • LinkedIn logo

Copyright © 2022 Sprecher + Schuh All Rights Reserved.

Legal Notices | Privacy & Cookies Policy

main logo