Keysight Technologies N5290/1A PNA Series Service Manual page 14

Safety and Regulatory Information
General Safety Considerations
Supply voltages which oscillate between the two normal input
ranges of the autoranging line voltage input will damage the power
supply. In rare cases, this damage has become a user safety
concern. If unstable power levels are expected, the analyzer input
power must be buffered by a line conditioner.
Before switching on this instrument, make sure
— the correct rating service breaker.
— the supply voltage is in the specified range
This instrument has auto-ranging line voltage input, be sure the supply
voltage is within the specified range and voltage fluctuations do not to
exceed 10 percent of the nominal supply voltage.
Do not operate the analyzer with the outer cover removed for more than
30 minutes, as this could cause the analyzer to overheat which could
result in costly damage.
Ventilation Requirements: When installing the product in a cabinet, the
convection into and out of the product must not be restricted. The ambient
temperature (outside the cabinet) must be less than the maximum
operating temperature of the instrument by 4 °C for every 100 watts
dissipated in the cabinet. If the total power dissipated in the cabinet is
greater than 800 watts, then forced convection must be used.
1-4 Keysight N5290/1A Service Guide