SD2 trip resolver monitoring regarding wire breakage, on the hardware side

Question:  
How is the SD2 resolver monitoring executed in case of the 9400, 9300 and ECS devices?

Answer:
9300 and 9400:
In case of controllers 9300 and 9400 the SD2 resolver monitoring is an interruption / wire-breakage monitoring of sine, cosine and ref regarding hardware side.  The individual monitoring of each sign refers to wire-breakage only, not to short-circuit.
The reaction time of the monitoring is in range of 0.1s, so the monitoring isn´t sensitive for short term signal interruptions but long term wire-breakage will be detected securely.  

The resistance threshold value 'programmed' via the hardware connection, where wire-breakage is started to be detected, is approx. 100 kOhm. This threshold exceeds the typical impedance values of resolvers by factor 100. Consequently,  An error 'SD2-Trip' occurring by mistake due to dispersions of resolver impedance values can almost be excluded.

ECS servo system:
In case of the ECS servo system the SD2 resolver monitoring of sine, cosine and ref regarding interruption / wire-breakage is executed via the software.
The signal amplitudes of the sine and the cosine track of the resolver are evaluated; the signals generally have to be in a certain relation to each other. In case of deviations an SD2 trip is triggered due to a lot of interferences, due to an interruption of the signal cables or due to a defect within the resolver.

All:
If an SD2 trip has occurred and the Lenze standard resolver cables are not used, a polarity reversal of the tracks could also be a probable reason.

URL for linking this AKB article: https://www.lenze.com/en-de/go/akb/200704634/1/