Two Nights to Remember
The Big Box Center Electrical Service Repair
It was 4:00 PM Thursday, June 6th, and I was at the Circle K at Chiquita and Cape Coral Parkway getting gas when I received a call from my brother and business partner, Anthony. “Whatever you’re doing, turn around and meet me at the Big Box Center in North Ft. Myers. They have a problem with their main service. They are out of power, and the fire department is there.” We have been doing service work for this facility for years, and Dan Carey, our Service Manager, has been the direct contact with them and was already on the scene.
We arrived shortly after and were greeted by LCEC (Lee County Electric Coop), the North Ft. Myers Fire Department, and a group of concerned store managers. Upon quickly assessing the condition of the main switchgear and the LCEC transformer and terminal cabinet, I knew we had a huge problem on our hands.
The main service consisted of 2500 and 3000 amp, 480 volt, three phase main circuit breakers, each feeding half of the building. Both sets of service entrance conductors, totaling eleven sets of 750 KCMIL copper conductors, entered the GE switchgear in the 3000 amp circuit breaker section. A hole had been cut in the left side of the section allowing five sets of the conductors to pass through and feed the 2500 amp circuit breaker. Much of the cable insulation in the bottom of the switchgear was burned off, and it was obvious that smoke and heat had risen through the cabinet, up the rear wall of the building, and traveled through the store.
As I approached the worried store managers, I knew we had a big problem here that wasn’t going to be easy to fix. As time went on, it became even more than I originally expected. Of course, their main concern was when they could expect to get power restored. At the time, we could not really be sure. However, we estimated a day or two if we only needed to replace the feeders and 3000 amp main circuit breaker.
At that point, I knew we were invested and needed to take whatever steps necessary to restore power to this 100,000 square foot facility and very important, long-term client of ACRA Electric, Inc.
We began by calling in employees to begin the tearout process. We then started the process of locating materials – especially 750 KCMIL copper cable, which is not stocked locally – that we knew we would need.
Our main concern focused around the condition of the 480 volt GE switchgear which had been subjected to heat and smoke damage and which we knew would be a lead time situation at best. Because it was a GE breaker, the first call I made was to the local GE rep, Jed Perkins, who came to the site and looked over the situation. The 3000 amp main breaker was an obsolete device, built in 1994. His suggestion was to call Emerson Electrical Reliability Services, a company specializing in testing electrical installations and equipment. Their field technician, Mike Smith, arrived at the site and confirmed that the 2500 amp circuit breaker and bussing were fine, but he was concerned about the condition of the 3000 amp circuit breaker, bussing and enclosure. We elected to remove the breaker and have Mike take it back to his shop for testing while we continued to pursue other options (including purchasing a used or remanufactured breaker that could be flown in), if necessary.
Our goal on Thursday night was to remove the service feeders and damaged bussing from the switchgear. The overnight cleaning crew would work on removing the carbon and soot from the metal surfaces of the cabinet. We contacted Tim Leigh, a fellow electrical contractor who specializes in crane work, and started pulling out the old feeders. That was when I realized that Plan A was out of the window.
As the feeders came out, the extent of the damage became evident. Many of the conductors showed evidence of severe heating – insulation was gone, wire was melted to the conduit, and some of the wire just broke off in the pipes as they were pulled. I knew by that time, the only way to be able to provide service to this building was to find a new way to feed the 2500 amp service from overhead and hope that out of the 11 existing conduits, there would be at least six that could be reused to feed the 3000 amp service. We came up with the idea of coming out of the top of the 2500 amp enclosure, through the rear wall, and down the outside of the building into the LCEC enclosure. Dan Decarufel, the manager of the local World Electric Supply office, came to the site, and together, we compiled a list of materials for delivery first thing in the morning, along with a list of wire that would have to be sourced from Orlando and Miami.
We left the site on Thursday night at 11:30 PM. On the way home that night, I received phone calls from building managers from the store’s home office and Bill and Steven from Rexell, offering help and support with the project. They arranged for a gentleman from GE Energy Management, Humberto Centeno, to contact me regarding the condition of the switchgear. I partnered him with Mike from Emerson, and they collaborated on the testing and certification of the circuit breaker, ground fault system, and bussing of the switchgear.
7:00 AM Friday: Knowing we had a big day ahead of us, we pulled our whole commercial department together and cancelled our scheduled work for the day. We loaded up our backhoe, pulling equipment, generator, work lights, scissor lift and headed back to the site. Humberto came to our office at 7:30 AM to work with Anthony on repair of the bussing. I went to the site to meet the Lee County Chief Electrical Inspector, George Barber, to review the scope of work at hand and our plan of how to proceed. He gave us some valuable insight and was fully supportive of our plan. He expedited the issuance of our electrical permit and had discussions with the fire officials while he was on site.
Our guys jumped on this project with determination and overcame obstacles as they occurred. We had to drill five 5” holes through the 12” thick rear wall of the building. One hole had three rebars and took almost an hour to core drill. When we started excavating, we discovered the building footer interfered with the five new 4” conduits, so we had to cut and chip out enough of the footer to provide clearance for the elbows. As we continued to excavate, we discovered that the six existing conduits we planned to reuse were compromised. The conduits were melted, distorted, and unusable. We managed to cut out all of the damaged material and had World Electric deliver enough additional material to replace the six conduits along with the new five that we originally planned to replace. By about 4:00 PM, we were finally ready to pull wire! The additional work had set us back about 5 hours, but we were able to get all of the new conductors installed in the conduits before dark, and now the tedious task of landing all of those conductors on the switchgear began. In the meantime, Anthony and Humberto reinstalled the bussing and 3000 amp circuit breaker.
LCEC’s employees, who had been patiently standing by, jumped into action and began the process of reinstalling their terminal cabinet and landing all of their conductors and ours – a total of 68 connections. Extreme care was taken to properly mark each conductor with proper phasing and color coding.
By about 11:00 PM, all of the wiring inside the building was complete, and Mike from Emerson was called back by Humberto to do final testing of the installation. Once they were comfortable that the system tested okay, I informed LCEC that we were ready to accept power.
Now it was LCEC’s turn to test their system. Two of their pole fuses had blown, so they first replaced them and then energized their primary underground distribution loop without the transformer. Once they were satisfied the loop was intact, they connected the primary conductors inside the transformer and reenergized the system, making the transformer and our service entrance conductors hot. Everything was going well so far. Once they tested rotation and their metering, we were given the green light to turn on our main switches.
At 1:15 AM Saturday, wearing a full arc flash suit and taking all precautions, our electrician, Ron Bula, pushed the buttons to bring power back to the panelboards. One by one, he then turned on each branch circuit breaker to restore full power to the building. This was followed by the cheers of the store staff members who were working inside the now lit up building!
The last thing we needed to check before calling it a night was the rotation of the three phase system, which was accomplished with the help of a refrigeration contractor called by the store owner. We left the site at 2:15 AM on Saturday, June 8th.
The big question is – what caused this to happen? Our collective opinion, based on what we saw during the process of completing this project, is that one or more of the service conductors could have made contact with the metal cabinet in the switchgear, compromising the insulation and beginning a process of heating which continued over a long period of time – even years – until enough insulation melted to cause a direct short, resulting in fire and tripping of the primary fuses. The earth surrounding the service feeders was still warm 30 hours after the service was disconnected. It is possible that the storm and possible lightning that occurred before the outage was the last straw that finally caused the system to erupt, but we do not believe it was the root cause.
Thanks to Dan Decarufel from World Electric for expediting materials and personally delivering them to the site, to Jed Perkins for his assistance, and to Dan Higginbotham for rounding up a large CT Cabinet during his company moving day. Thanks also to Tim Leigh for his crane and expertise.
Thanks to Mike Smith from Emerson Electrical Reliability Services for working late Thursday and Friday nights to assure the safety of the equipment. Thank you to Humberto Centeno from GE Energy Management who, in addition to collaborating with Mike, also helped us with cable cutting and pulling.
Thanks to George Barber from Lee County Code Enforcement who expedited the permit and approval process.
Thanks to Charlie Morris and his team from Lee County Electric Coop. They went above and beyond to minimize the downtime and also to assure our safety.
Thanks to all of the managers and employees of the store for their gracious understanding of the situation and their ability to quickly help us in any way they could with each request, such as providing refreshments for the crews, forklifts, etc.
Special thanks to the crew of ACRA Electric, Inc. who went above and beyond, working long into the night with no breaks, to diligently and competently complete the tasks and overcome the obstacles as they occurred.
Thankfully, during this whole process, no one was injured. The fireman who approached the energized switchgear and shut off the two mains was at great risk. Since the fault was on the line side, an arc flash could have occurred with the movement of the switch. Possibly because two of the three pole fuses had already blown, this didn’t happen. It is my understanding that the Big Box Store re-opened for business at 9:00 AM on Saturday – a glorious ending to two nights I’ll never forget!
ACRA Electric, Inc.