In datasheet table 5 it says: "Highest Allowable Overvoltage Transient
overvoltage, tTR = 10 seconds VTR 4000 V peak" . Does this mean that isolator
can withstand standard like (IEC61000-4-5 Level 4) 4 kV surge test? What about
standard IEC60255-27 5kV impuls test?
The 4000Vpk test is an agency proof test done by VDE. It's an isolation voltage
test, done with a sine wave at 60Hz.
For Table 5, VDE V 0884-10 is for reinforced insulation rating and we do a
surge test not shown in the table, for a reinforced rating of 6000V pk, which
requires a 10,000V pk surge, which is 1.6 times the 6000Vpk rating for
reinforced, per VDE standard. So we meet 10,000V pk surge, more than these
other standards. It is a 1/50us test waveform, like the IEC61000-4-5 test.