| Answer:
Remove them very carefully. If you look closely at the way the knockouts are stamped
on the electrical sub-panel you will
see that they alternate between getting punched in and getting punched
outwards. Usually you would start with the
smaller center KO first, but I usually
go with whatever is easier and most convenient
for each job. I use a hammer and an
old screwdriver for making the first
punch.
Once you get it
started by hitting with the screwdriver you need to twist
it or knock it forth and back a few times to loosen it up. If you have a good pair of
diagonal pliers or BX cutters you can sometimes get in there and cut one or
more of those welds or the ring itself. Just don't try to get it real fast. Be patient and
work it out. You will feel the knockouts get looser as you move them forth
and back.
For subsequent
rings sometimes you use can use your pliers to carefully pry
the ring halves until they are up enough to
squeeze them together and then rock back and forth
parallel to the anchor point until it breaks off. If you try to rock in
the other direction it will tend to twist the next ring up.
Just keep removing the rings in the
direction that they were punched and
you should be fine.
In a
situation where the
electrical sub-panel
is recessed in a wall, you can use a long thin screwdriver
and stick it between the edge of the wall and the edge of the panel to apply a little
pressure on one of the rings from the
outside to get it started.
Each
electrical sub-panel manufacturer's concentric knockouts are
different in strength and ease of
removal. Sometimes they pop out
too easily and you have a much bigger
opening then you need.
Fortunately there are reducing washers
made to transition from the larger
opening to the size that you
need. These can be purchased at
almost any electrical supply company. |
