When doing maintenance on an Uninterruptible Power Supply and its auxiliary equipment, keeping it clean is one of the main objectives. Dirt, dust, sawdust, and metal filings are just some of the pollutants that technicians see in UPSs, even when installed in seemingly clean environments. These substances can cause failures when they contaminate the contacts of relays and contactors, and conductive material can cause short circuits and malfunctions on printed circuit boards (PCBs).
At least once a year, make sure your UPS gets cleaned including a good vacuuming with a non-conductive hose and attachments. Never use a blower or compressed air! These methods can blow contaminants deeper into the unit, causing real troubleshooting headaches if and when they finally do cause issues.
Use lint-free rags lightly damp with a nonflammable and fast-drying solvent for heavy deposits, and soft brushes around delicate components and connectors. Always perform cleaning work on equipment that is offline, and de-energized and with the proper personal protective equipment (PPE) such as goggles, gloves, aprons, and respirators as necessary. Lastly, always use a torque wrench on copper and lead connectors
