TIDUDJ6B August 2022 – February 2023 OPA388-Q1
Simulate an isolation error condition by connecting the chassis ground line to HV positive. Change the switches on the load card appropriately to support the same. To understand the behavior of error conditions, the measurements were performed at different battery voltages.
No resistance from positive line to chassis ground | |
CH1: ISO_POS CH2: ISO_NEG CH3: RELAY_NEG CH4: RELAY_POS | |
100-kΩ resistance from positive line to chassis ground | |
CH1: ISO_POS CH2: ISO_NEG CH3: RELAY_NEG CH4: RELAY_POS | |
HV BATTERY VOLTAGE (SUPPLIED AND MEASURED) | MEASURED REFERENCE VOLTAGE | MEASURED PEAK ISO_POS VOLTAGE | MEASURED PEAK ISO_NEG VOLTAGE |
---|---|---|---|
100.006 | 2.505 | 2.606 | 3.027 |
150.008 | 2.504 | 2.606 | 3.236 |
200.003 | 2.504 | 2.608 | 3.444 |
250.004 | 2.504 | 2.608 | 3.652 |
300.004 | 2.504 | 2.608 | 3.861 |
350.004 | 2.504 | 2.608 | 4.069 |
400.006 | 2.504 | 2.608 | 4.278 |
450.007 | 2.504 | 2.608 | 4.484 |
#T5081059-35 shows the deviations of HV POS and HV NEG ADC voltages from the normal conditions. HV POS is above the reference voltage when U6 (positive relay) is closed. This behavior is observable only when the HV positive line is low ohmic or short to chassis ground.