Managing water-damaged equipment safely
News coverage this summer has been fraught with images of the destruction and, unfortunately, deaths due to hurricanes Dennis, Emily and Katrina. Sadly, this destructive triumvirate most likely will not be the only names we will hear before the hurricane season concludes in November. As of late August, the National Oceanic and Atmospheric Administration was predicting 11 to 14 more tropical storms, including up to five major hurricanes.
But hurricanes are not the only weather calamities that can cause water damage to electrical distribution and control equipment. Floods caused by both hurricanes %%MDASSML%% as of this writing, 80% of New Orleans is underwater due to Katrina %%MDASSML%% and heavy thunderstorms can cause serious weather damage. That means no matter where you are in the United States, you may be facing frantic questions from customers in the wake of a natural disaster, wondering whether their equipment can be dried out, are their circuit breakers OK to use, can their switchboard be re-energized?
There may not be a more appropriate time than the present to review rules regarding water-damaged equipment. Adhering to these rules will make your customers feel safer; reminding them of the rules will make you a good neighbor.
Types of water damage :
The simplest rule of thumb is this: Electrical equipment that has been submerged must be serviced or replaced . Attempting to dry out the equipment in many cases leaves portions of the current-carrying parts with damp or wet surfaces, which may be in contact with insulators or other materials that prevent them from being properly dried out and cleaned of debris. Residual debris or wet surfaces could result in a loss of dielectric spacing within the equipment and could be hazardous upon re-energization. In addition, hazardous conditions can develop after re-energization if untrained personnel try to disassemble and reassemble equipment.
For certain types of equipment, such as switchboards, switchgear and medium-voltage circuit breakers, reconditioning may be possible, but the ability to do so will vary and may include repair or replacement of internal components or of the complete circuit breaker. (See Figure 1 for lists of equipment that must be replaced and could be reconditioned.) Disassembly should be performed only by trained factory service personnel who are familiar with equipment design and function.
If your customers have equipment located in flooded areas but it was not submerged, it should be inspected by a qualified person to determine whether moisture has entered the enclosure. If there are any signs of moisture or damage, the equipment should be replaced or repaired.
Resources are typically in place from manufacturers to help customers evaluate water-damaged equipment and make recommendations. For example, in the wake of Katrina, home and business owners with concerns about the operation and safety of damaged electrical systems and equipment were able to call Square D’s Customer Information Center toll-free around the clock to speak to experts about the correct course of action to safely restore electrical systems. Additionally, Square D also activated its “WE CARE” program in FEMA-declared disaster areas in several states to address public safety issues and support electrical personnel as they repaired damaged electrical structures and systems, in addition to expediting orders for electrical products to aid in the reestablishment of electrical systems.
Other considerations :
What if your customer has equipment with field-replaceable interior components? Generally, this situation is limited to a load center or panelboard product where the entire interior assembly can be removed and replaced as a unit. It is possible that enclosures can be reused in this situation if they have not been subjected to physical damage and if they have been properly cleaned of all debris and foreign materials. Consideration must also be given to other components in the electrical system, such as conductors (wire, cable andbus), junction boxes, and termination points.
Be sure to make customers aware that certain kinds of cleaning agents, especially petroleum-based cleaners, can be hazardous when applied to the current-carrying portions of electrical equipment to remove debris or residues. Additionally, some cleaning and lubricating compounds can cause deterioration of non-metallic insulating or structural portions of equipment. Abrasives or sandpaper should not be used to clean current-carrying parts of equipment.
The only thing you can predict about natural disasters and flooding caused by lesser weather events is that they are going to occur. It is never an ideal situation, but any information you can provide to customers after a calamity %%MDASSML%% or better yet, before %%MDASSML%% is going to increase their chances of survival.
Mike Rice is the director of Square D Services, a division of Schneider Electric, based in Palatine , IL