Troubleshooting
1
Keysight RP7900 Series Advanced Service Guide
21
Isolation and isolation attic board operation
– The isolation board consists of a H bridge circuitry that can step up and step
down the voltage to the required voltage level. Its main function is to provide
the isolation between the primary and secondary circuits. It receives the DC
voltage from the AC front end and then adjusts the voltage level to 565 V. The
isolation attic board consist of a transformer and over-current protection
circuitry.
– The isolation board protects itself from ‘live’ conditions, such as local over
temperature (OT) and rail over voltage (OV) or low voltage (LV). The source of
a rail OV/LV will either be an issue with its input, an internal malfunction, or a
regulation board malfunction.
