Because mobile generators are a common piece of equipment on oil and drilling jobsites, they are often not treated with enough caution. As a result, an average of one worker is electrocuted on the job every day each year. Understanding the inherent dangers of electrical equipment and how to lessen those risks is the foundation of working safely.
Mobile generators, in particular, present different risk factors than stationary generators because of their ability to be transported between jobsites. During transport, a mobile generator’s external and internal components are often exposed to rough conditions that have the potential to jar, jostle, rub and loosen machine connections. Practicing specific steps and checks between every job can lessen the electrical risks of operating a mobile generator for you and the members of your crew.
When a mobile generator arrives on site, be sure to inspect load connections to confirm nothing was jarred loose in transport. A generator operating at peak performance one day may not be safe to operate at the next jobsite after bouncing over potholes or traveling down a makeshift dirt road.
Electrical connections need to be mechanically tight to maintain a low resistance across the connection — ideally 0 ohms. When voltage flows through a loose connection, power is dissipated in the form of heat, which can burn the connection, scorch wiring and damage the generator. More importantly, any time a connection becomes loose, it increases the potential for the energized circuit to come in contact with an unintended surface, which creates the risk of shock.
All wiring should also be inspected upon arrival. Wires have the potential to rub through insulation during transport. Exposed wires can charge a piece of sheet metal, energizing the frame of the generator and creating a very dangerous situation for anyone who comes in contact with the machine. Encountering an energized machine can cause electrical current to flow through the body resulting in electrical shock, burns, critical injuries or even death.
Grounding is another important safety task that must be completed when a mobile generator arrives at a jobsite. Grounding a piece of equipment involves creating a path of least resistance to carry current traveling outside its intended path to the ground, typically through a copper rod or stud. Grounding reduces the risk of serious injury to operators and laborers. If a fault occurs without grounding a generator, current flowing outside its intended path poses a serious threat to anyone in the area, including electrocution and even death.
Stationary generators are grounded upon site installation, but mobile generators must be grounded upon arrival at each jobsite. Operators should follow all local electrical regulation codes for properly grounding equipment.
Generator equipment should be inspected for moisture between jobsites. Any type of moisture inside the generator increases the risk of water entering the alternator. When water enters electrical components, it can cause a short circuit. When a generator experiences an electrical short, it causes permanent damage to the generator, but can also result in sparking, fire and arcing. An arc flash exposes an operator to an electrical explosion that produces light, flames, heat and molten metal hazards.
Inspecting a mobile generator for moisture between jobsites reduces those risks, but it also presents an opportunity for training. Generator doors should be closed during operation to prevent moisture from entering the unit in the form of rain or condensation buildup. Enclosures are sealed to prevent moisture penetration in wet environments.
Downtime between jobs is an ideal time for safety training and review without the distractions and limitations of a working jobsite. Taking time to ensure your employees understand the potential hazards of electrically energized equipment and how to exercise safe troubleshooting procedures is an investment in the future of your people and your business. Following all Occupational Safety and Health Administration (OSHA) standards and National Fire Protection Agency (NFPA) 70E guidelines will also help ensure safe working conditions.
For occasions when downtime between jobs is more than a day or two, there are additional actions that can be taken to improve generator safety. Mobile generators should be connected to a load bank between jobs to validate that the alternator is producing voltage and electrical current to its rated capacity. Load banking, as it’s often called, may also identify problems that could hinder generator performance at the next jobsite, but can be resolved before leaving the shop. Operating a generator on a load bank also cleans up any emission issues that the engine may be experiencing due to light loading from a previous job.
Working safely is the most important job you can complete on a drilling site. That starts with being aware of the potential dangers of mobile generators, properly operating all electrical equipment, and having safety protocols in place to protect you and your employees.