When I removed the cover it almost fell back into the panel. Top screw was missing.
Inner cover
Got it, thanks.
A potion of the pin mechanism connecting the Interior Trim to the Flush Cover is missing…
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Deadfront…
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That’s exactly what it’s called around here, the “interior trim”. On commercial panels you have the outer cover with the hinged door and the separate and separately fastened interior trim that surrounds the circuit breakers.
This panel is a load center that doesn’t have a separately attached inner panel. Someone turned the adjustment screw out too far and it came lose.
“IF” you would have seen this before you removed the cover - you should have stopped and called it out as a defect.
The panel should be de-energized before removing this cover.
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Michael
I think you already know so I’m only raising this issue for the education of those who are less experienced. First a caveat. The terms I use will be taken from the US “National Electric Code.” Most of the “Panels” that home inspectors need to look at are; in addition to being Lighting and Appliance Panel Boards; the Service Disconnecting Means. By that I mean that the cabinet that you need to remove the cover from is also the Service Disconnecting Means enclosure. Please notice that I did say most.
That raises 2 important issues. The first issue is that it is often impractical and sometimes nearly impossible to de-energize the supply to that equipment completely. Opening the panel’s main breaker. if it has one, will de-energize everything in the cabinet except the Main Breaker’s supply lugs. If that breaker is also the Service Disconnecting Means then there is no practical way to de-energize that breakers supply terminals. In the US those terminals may be exposed to accidental contact with the metal cover during the process of removing it. If such contact should occur the person removing the cover may receive a dangerous or even fatal shock. Additionally the fault between the supply terminals and the cover are almost as likely to cause an arc fault. An Arc Fault is a truly dangerous event that can generate so much heat and light that an exposed person can suffer life threatening burns instantaneously. The amount of energy available to the supply terminals in a residential service equipment enclosure is limited by the voltage and the impedance of the conductors between those terminals and the utility’s transformer. Those factors tend to limit any arc flash to a survivable level but not to a level were injury is unlikely. Being a retired electrician I am unfamiliar with the safety standards of the home inspection industry but the personal protection standards of the electric industry are or have changed very radically. To be in compliance with the Occupational Safety and Health Administration’s rules an electrician who is opening or working in such a panel must be dressed in clothing that completely covers all of their body leaving no skin exposed. The clothing worn must be ignition resistant and capable of protecting the wearer from an identified level of flash energy which I do not have memorized. If you were to look at an electrician who was dressed in compliance with that standard the clothing worn would look quite ordinary. It would have the appearance of a set of ordinary work wear but would include gloves, googles or a face shield and a non conductive hard hat. If that electrician were going to work in that panel they would also don a pair of class ØØ (said aught, aught) gloves that are insulated to 500 volts AC. Those gloves would be covered by gloves which serve to protect the insulated gloves from physical damage that would compromise the insulating protection they provide. This is, for many of us, a completely new way of going about electrical work. It takes some getting used to and until the industry is staffed by electricians who have been trained to do it this way from their first day on the job a lot of unprotected work will continue to occur.
I remind all of you of this because, even though you will still see a lot of electricians who do not work in compliance with the new rules, electrical work is undergoing a true sea change in safety practices. I am not going to presume to tell you how the home inspection industry should conduct it’s work. What I am suggesting is that your industry may need to take a hard look at your present practices and see if they have kept pace with the standards of all the crafts who’s work you have to inspect.
Let me insert a comment about what is considered by most electrical workers, including utility linemen, to be a truly dangerous practice. That practice is the pulling of electrical meters out of their enclosure sockets as a means of de-energizing Electrical Service Disconnecting Means enclosures. If you see an outside wireman pulling a meter you will notice that they keep all of their personal protective equipment on when doing this job. They also will have opened the circuit at the Service Disconnecting Means where that is possible. The particular concern here is that the meter’s enclosure mounting jaws were never designed to serve as a switch. Electrical Meters were never designed nor tested to serve as a Pull-Out disconnect. The older the meter enclosure the greater the chance that it will expose the person who is removing the meter to an Arc Fault event.
The additional hazards for those who engage in this practice are that not all metering arrangements pass all of the current to the Service Disconnecting Means through the meter. This is even true at ampacities as small as 60 Amperes. A significant number of Meters used in US practice are connected to Current Sensing Transformers which have no affect on the supply to the service other than to measure the amount of current flowing by sensing the magnetic field around the supply conductors. Many meter enclosures intended for use at capacities between 225 amperes and 400 amperes have meter bypass mechanisms that are used to avoid the likelihood of arcing during insertion or removal of the meter from it’s mounting jaws. Some of those bypasses are automatic in that when you open the cover of the meter enclosure the bypass or shunt will close in parallel with the meter so that the removal of the meter will not disconnect the flow of current thus avoiding the likelihood of a switching arc. The rather obvious side affect of some of these meter mounting arrangements is that removing the meter will not necessarily disconnect the power from the Service Disconnecting Means supply terminals. Based on over 50 years of experience in the electrical industry and 45 years of serving as an active volunteer in Fire and Rescue work I am fully confident is saying that pulling meters should be left to fully trained and equipped electrical practitioners!
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Tom Horne
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At the risk of seeming to be pedantic I will point out that the US National Electrical Code does not have a definition for a “Load Center.” That particular panelboard is not fitted with a Dead Front cover that is not part of the cover. The definition of a dead front describes an outcome and not a particular style of construction. In common usage in the electrical industry a dead front is a cover over the energized parts of a panelboard, switchboard… that is still in place once the cover is removed. The US National Electric Code (NEC) defines Dead Front as:
“Dead Front. Without live parts exposed to a person on the operating side of the equipment.”
How the equipment designer achieves that outcome is not withing the scope of the NEC. For Home Inspectors I would think that it would be important to avoid the undefined terms that are common in any craft. If the language used has no well excepted definition would that not expose your report to attack?
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I just call what the OP posted as an inner (dead front) cover.
But it’s not what electricians mean when they talk about a dead front. In the craft a dead front is a completely separate interior piece that continues to cover the breaker terminals even after the outer cover has been removed. What the OP showed in the photograph was an outer cover that is fitted with a self depth setting trim. If one of the adjustment studs had not been broken it would have come off cleanly once the cover screws are removed. Real Dead Fronts are separately fastened to mounts inside the panel cabinet. To get at the terminals of the breakers you have to remove the cover and then unscrew and remove the interior terminal shield that is commonly called a dead front.
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Tom Horne
