Troubleshooting
1
Keysight RP7900 Series Advanced Service Guide
15
Before, During, and After Troubleshooting
1 Before turning on the unit under test (UUT):
– Make sure all connections are done correctly.
– Connect the 3-phase power cord to the UUT before connecting the plug to
3-phase main power trunk.
2 During test:
– DO NOT probe any area of the UUT as there is HIGH RAIL VOLTAGE present
while the UUT is powered ON.
– If you wish to measure any test points, always ensure that the DMM probes
stay on the measurement area before powering on the UUT.
3 After test:
– Turn off the UUT and all other testing equipment.
– Unplug the 3-phase power cord immediately.
– DO NOT touch any location of the UUT as the HIGH RAIL VOLTAGE is slowly
discharging (the RAIL LED is
RED
).
– Wait 5 minutes or until the RAIL LED is
OFF
before performing any
disassembly procedure.
