One photo is a close-up of the wingnut and the other is an overall picture of the panelboard. On this panelboard the front cover is secured by screws on the bottom and the use of wingnuts on the top. Is this a violation? I think the fastener should require the use of a tool to remove.
Not that this is really any excuse for doing this, but...I wonder if this was done in an effort to allow one man to remove and replace one of these enormous covers without assistance (or cribbing the bottom edge of the cover). I had the occasion of seeing a sparky, working solo, trying to remove a SqD I-line MDP panel cover (measuring about 3 1/2' wide by 6' high and weighing god-only-knows how much) and using paint cans, pieces of lumber, etc. to support the cover. I took pity on the guy and stayed around for a bit to help him grunt that thing off the panel and back on again...
A "foot" on the bottom of the cover, two well placed 1/4-20 x 1" bolts on the top, thru from the inside, and two 1/4-20 wing nuts, and it's a one man cover. The above formula works on virtually all brands of panels. It's the "lone sparky's" helper. The other screws should satisfy the " tool required" to remove comment, as even if you opened the teo wing nuts, you still need a "tool" IF the balance of the screws are installed.
Cutler Hammer has wing nuts on the pull and CT sections of switchboards from the factory. The "bolt" is drilled to accept the utility co. seals, and the wing is drilled also, so the seal can pass thru.
The little "foot" for a panel support on the square d panels are a great idea. How many of you get right pissed when you take off the panel cover only to find the main conductors(usually 500's) running right behind the front and spring out towards the front of the panel so the little "foot" won't fit between the conductor and the lip. Gets a bit tense when time comes to put that sucker back on Live.
The Company I work for always orders Hinge on Hinge covers and during construction we put one bolt in backwards and use a wingnut on that one bolt. This keeps the panel closed but is to open to work on. When we finish the factory hardware is put back but you still have the ease of the extra hinge.
Bob Badger Construction & Maintenance Electrician Massachusetts
That Subpanel cover looks like one of those nice old 150 Lb, 6 foot long, flimsy as Jell-o covers used on Zinsco type 42 space Subpanels with intregal Lighting Contactor Cabinets (typically housing an 8 pole Asco Lighting Contactor and a Tork Timeclock).
Those covers are a major pain to replace - even by Two people!!! Mainly due from trying to manipulate the cover so it lines up with the floating nut assemblies on the can, and trying to start threading a bolt while that floating nut moves everywhere!!!
I wish I had thought of replacing the top bolt with a fixed stud, then locking down the cover with a wingnut!!! I am serious!!! This would have eliminated curse word sessions, dropping of covers when bolts did not start as expected, sweating for 10 minutes per panel cover, the possibility of a "Wild / Twisting / Falling / Hell-Bent" panel cover falling into the subpanel or shearing off insulation while it falls straight down - not to mention the broken toes resulting from those darn things falling straight down onto someone's foot!
As long as this would not be a Compliance Issue, I would like to try it next time I run across one of those F..,,,... err.. Fine panel covers!
Scott " 35 " Thompson Just Say NO To Green Eggs And Ham!