Salvaging flood-damaged equipment is it possible?
When Hurricane Sandy hit the east coast back in October 2012, no one could have anticipated the destruction and devastation it would leave in its wake. Homes and businesses were destroyed, power outages lasted for well over a month and flood damage was everywhere you turned. This was something that no one in the area had seen in recent years -- something that no one was prepared for.
Because of the massive amounts of rain, wind and flooding the east coast endured, a wide variety of electrical equipment had been damaged including rotating electrical machines that generate power, switchboards and electrical controls, transformers, cable and wiring and electrical tools.
Much of the damage done was to expensive equipment that many worried was not salvageable. Because of the nature of our business, Megger was able to step in and help out many companies on the east coast, offering tips and suggestions about how to dry out their electrical equipment and what products to use to test flood-damaged equipment before putting it back to work.
One of the most important tips we offered was not to test any equipment until the electrical windings had been completely cleaned and dried. No voltage should be applied to a winding until it has an insulation reading of at least 100,000 ohms and is obtained for several hours. Megger's MIT400 Series, MIT320 and MIT330 have kilohm ranges that work perfectly to test this.
For environments post-catastrophe where there is no line power available and batteries are in short supply, we offer Major Megger, a tester that features always-ready hand-crank operation. Major Megger measures to only 6 V, ensuring that no further damage will be done to even the worst of insulation. Flow should be limited to only a fraction of nameplate amperes and a careful check must be maintained on maximum temperatures on the insulated parts. Welding sets may be used to provide current.
We had heard that many DC motor and generator field coils from synchronous machines were presenting problems after the storm and flooding. In an effort to diagnose what was going on and remedy the problem, it was necessary for technicians to remove these coils from the machines for proper treatment if it wasn't possible to bring up the insulation resistance otherwise. Using Megger's DLRO10HD digital low resistance ohmmeter helped indicate open coils and determined shortened turns by the reduction in resistance that turn-to-turn shorts produce.
Many oil pans on starters and oil switches needed to be cleaned, dried out and refilled with oil because the proper dielectric strength after flooding was out of balance. We recommended using our OTS60PB and OTS60SX Oil Test Sets to restore proper dielectric strength in an effort to help those faced with that situation.
Offering assistance and knowledge to those trying to cope and recover after devastation caused by a natural disaster is something we at Megger take to heart. By giving our customers the information and tools they need to repair their equipment and get themselves back up and running again is paramount to us.