Technical FAQs

Ask a Question

What is the difference between an I-Line Blank Filler and Blank Extension?

Product Line:

Panelboards, Switchboards

Environment:

I-Line Combo Panelboards, I-Line Panelboards, I-Line (QED) Switchboards

Cause:

With the introduction of additional blank extensions for use with advanced trip unit circuit breakers it has become more difficult to determine the correct application for both blank fillers and blank extensions.

Resolution:
  1. Blank Fillers
    1. Blank fillers are used to cover the bus bars of unused circuit breaker mounting space on single row and double row interiors.
    2. Blank fillers attach to the interior mounting pan with screws (21593-20100).
    3. Blank fillers come in two sizes.
      1. HNM1BL (40517-408-01) - This is a 1.5" wide blank filler.
      2. HNM4BL (40517-407-01) - This is a 4.5" wide blank filler.
      3. By using combinations of these two fillers any size of unused breaker mounting space can be covered.
  2. Blank Extensions
    1. How blank extensions are used.
      1. First, if a blank filler does not fill the entire opening in the trim then a blank extension is used to fill the remaining space and overlaps the blank filler.
      2. Second, if a smaller frame circuit breaker is installed but does not fill the entire opening in the trim then a blank extension is used to fill the remaining opening in the trim and overlaps the circuit breaker.
      3. Blank extensions snap onto a mounting rail on the bottom side of the trim and require no screws for mounting.
    2. Selection and application of blank extensions.
      1. The following blank extensions are used on the narrow side of an interior.
        1. HLN1BL (80121-651-01) - This is a 1.5" wide extension used on the narrow side of I-Line panelboard and switchboard interiors, when anything is installed in that location except an H/J frame circuit breaker with a Micrologic 5/6 trip unit.
        2. HLN4BL (80121-652-01) - This is a 4.5" wide extension used on the narrow side of I-Line panelboard and switchboard interiors, when anything is installed in that location except an H/J frame circuit breaker with a Micrologic 5/6 trip unit.
        3. HLN4EBL (80121-752-01) - This is a 4.5" wide extension used on the narrow side of I-Line panelboard and switchboard interiors, when an H/J frame circuit breaker with a Micrologic 5/6 trip unit installed.
      2. The following blank extensions are used on the wide side of an interior.
        1. These blank extensions are used in conjunction with a circuit breaker.
        2. HLW1BL (80034-187-02) - This is a 1.5" wide extension used on the wide side of I-Line panelboard and switchboard interiors, when anything is installed in that location except an H/J frame circuit breaker with a Micrologic 5/6 trip unit.
        3. HLW4BL (80034-188-03) - This is a 4.5" wide extension used on the wide side of I-Line panelboard and switchboard interiors, when anything is installed in that location except an H/J frame circuit breaker with a Micrologic 5/6 trip unit.
        4. HLW4EBL (80121-653-01) - This is a 4.5" wide extension used on the wide side of I-Line panelboard and switchboard interiors, when an H/J frame circuit breaker with a Micrologic 5/6 trip unit is installed.

Note: Attached you will find an Excel spreadsheet with a color, pictorial representation showing how the blank fillers and extensions are applied and a PDF file of the blank extension installation manual.
Was this helpful?
What can we do to improve the information ?