Technical data

Service Guide N5230-90025 4-7
PNA Series Microwave Network Analyzers Troubleshooting
N5230C Power Up Troubleshooting
Power Supply Check
NOTE There are no fuses to replace within the power supply. If you determine that the power
supply is the failed assembly, replace the power supply.
A catastrophic failure in the power supply can be determined by observing the line switch:
1. Ensure that the instrument is plugged in with the power switch in the standby position (power not
switched on). Verify that the line switch glows yellow. A line switch that glows yellow indicates that
the +15 VDC line (P15 STB) is providing enough voltage to light the LED. (The actual voltage may not
be +15 VDC.)
2. Turn on the instrument power and verify that the line switch glows yellow. When the line switch
glows, it is an indication that the power supply has received an “ON” command and that the +5.2 VDC
supply can supply enough current to light, at least, these lamps.
If all of these supply voltages are missing, it is likely that the problem is either a defective A4 power supply,
or another assembly is loading down the A4 power supply. Continue with “If All Supply Voltages Are
Missing” on page 4-9, to determine the cause of the problem.
If the line switch is lit correctly the power supply has not suffered a catastrophic failure; however, the power
supply could still be at fault. Continue with the next section to measure the individual voltage supplies.