What safety precautions should I follow when using the HP DesignJet T520?

You should always use the power supply voltage specified on the label and avoid overloading the electrical outlet with multiple devices. Power off the printer and unplug the power cord if there is smoke, an unusual smell, an unusual noise, if metal or liquid touches internal parts, during an electrical storm, or during a power failure. Do not disassemble or repair the printer yourself — contact your local HP Service Representative instead. Never allow metal or liquids (except those used in HP Cleaning Kits) to touch the internal parts of the printer.