Remedied from:
ECSxA (ECS axis module application as of version 7.4)
and standard applications Speed&Torque, Posi&Shaft and Motion
Behaviour of new version?
When using resolvers with several pole pairs, the positions indicated in the system variables MCTRL_dnPos_p and MCTRL_nPos_a after mains disconnection correspond to those indicated before mains disconnection. It has to be considered, that for resolvers with n pole pairs, only an angle displacement of ±180 °/n in switched-off state can be detected.
Which products are concerned?
ECSxA (ECS axis module application up to version 7.1)
and standard applications Speed&Torque, Posi&Shaft and Motion
Problem description:
For multipole resolvers, the rotor position after mains connection is always referred to the first pole pair. This isn't suitable for an application which uses the resolver as an absolute measuring system after mains connection. The zero position of the absolute system then is selected at random.
When does the problem occur?
When using resolvers with several pole pairs.
Possible diagnostics?
Comparison of the values in C0060 (rotor position) before and after connecting the 24 V DC supply voltage.
Short-term measures/recommendations?
None.
Evaluation
Applications using a simulated absolute measuring system and resolvers with several pole pairs cannot be solved.
Information taken from chapter 2.6 of
Service Message No. 07/2007.
