This attribute displays whether the Unexpected Payload Type (UPT)
alarm state has been entered. The UPT alarm state is entered when
UPT defects have been observed and accumulated for a period of
2.5 seconds +/- 0.5 seconds. The UPT defect is reported when a
received frame fails to agree with the expected Payload Type. If the
UPT defects are intermittently occurring, the UPT defect
accumulator is decremented at a rate of 1/10 of the incrementing
rate (alarm integration ratio of 1/10), with all measurements based
on a 200 ms polling cycle..
The UPT alarm is cleared when the Payload Type in the received
frame agrees with the expected Payload Type for a period of 10
seconds +/- 0.5 seconds.
The unexpectedPayloadType attribute is always set to off when the
E3 component has been locked and left offline.