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Does Lexium SD328 support normally open or normally closed limit switch contacts?

Lexium SD328A and SD328B stepper drives support both normally open and normally closed type contacts for the I/O.

Users can change the parameter from  normally closed to normally open by modifying parameters IOsigLimN, IOsigLimP, and IOsigRef, depending on which inputs they choose to use and how they want them to behave.

The factory default setting is for normally closed contacts, this is for safety reasons.  
If the wire to the limit switch is broken, a normally closed contact setting would trigger a fault providing the operator with an indication that the wiring has been compromised, where as limit switches that use normally open contacts can have a broken wire and the drive will have no way to protect against overtravel.
This should be taken into consideration when deciding to use normally open contacts.

rev 7-2-18
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