Dismantling electrical systems requires extra precaution than many other systems.
Before a project can begin, a contractor must first identify what must be dismantled. Oftentimes in older facilities, electrical panels, motor control centers, and substations are not labeled properly, or are not labeled at all. It is important to avoid accidentally shutting off circuits that should not be turned off. Sometime this requires tracing circuits out and identifying what they feed before they can be turned off.
Proper lockout/tag out procedures must be followed when dismantling electrical systems. This includes logging and tagging the circuits out, then identifying that the circuit is off using a voltmeter. For transformers, substations, and all electrical gear, it is recommended that the gear be grounded so as to dissipate any potential energy. Sometimes, a potential difference or charge can exist in transformers capacitors, or other equipment. This should only be done by a licensed electrician to verify that no potential energy exists. Conduit and gear that is safe and ready for removal should then be identified with green spray paint.
Dismantling electrical gear often requires unbolting or cutting gear into pieces. Clients may wish to harvest particular parts in older equipment to set aside for spare parts, so this should be verified with the customer before commencing removal. When dismantling electrical conduit and boxes, all straps and supports must be removed, and it is important to plug existing openings from junction boxes and gear to national code requirement. Bolts, screws, and ground rods should be removed from equipment pads, as well. Where present, oil must be removed from transformers and properly disposed of.
Electrical dismantling is not for beginners and should be left to seasoned professionals.