4 Keysight 8990B User’s GuideSafety ConsiderationsThis is a Safety Class I instrument (provided with a protective earthing ground,incorporated in the power cord). The mains plug shall only be inserted in a socketoutlet provided with a protective earth contact. Any interruption of the protectiveconductor inside or outside of the instrument is likely to damage the instrument.Intentional interruption is prohibited.WARNING – Do not operate the instrument in an explosive atmosphere or in thepresence of flammable gasses or fumes.– Do not use repaired fuses or short-circuited fuseholders. For continuedprotection against fire, replace the line fuse(s) only with fuse(s) of thesame voltage and current rating and type.– Do not perform procedures involving cover or shield removal unless youare qualified to do so. Operating personnel must not remove the metercovers or shields. Procedures involving the removal of covers and shieldsare for use by service-trained personnel only.– Do not service or adjust alone. Under certain conditions, dangerousvoltages may exist even with the instrument switched off. To avoidelectrical shock, service personnel must not attempt internal service oradjustment unless another person, capable of rendering first aid andresuscitation, is present.– Do not operate damaged instrument. Whenever it is possible that thesafety protection features built into this instrument have been impaired,either through physical damage, excessive moisture, or any other reason,REMOVE POWER and do not use the instrument until safe operation canbe verified by service-trained personnel. If necessary, return theinstrument to Keysight for service and repair to ensure the safety featuresare maintained.– Do not substitute parts or modify the instrument. Because of the dangerof introducing additional hazards, do not install substitute parts orperform any unauthorized modification to the instrument. Return theinstrument to Keysight for service and repair to ensure the safety featuresare maintained.
