Hello I have similliar problem with my drive. Machine type Lathe "Trens SBL500" with simoidrive 810D.

One of spindle encoder was damaged Heidenhain on the chunk axis we have replaced that by new one but following errors still exist:

25000 Axis C1 hardware fault of active encoder

25001 Axis C1 hardware fault of passive encoder

300504 Axis C1 drive 3 fault of motor transducer

25201 Axis C1 drive fault

But encoders now is working showing both values but something still wrong

Then I was trying to change Axis MD 30200 to 0 and 30240 both to 0 and still can't run spindle have these errors:

300504 Axis C1 drive 3 fault of motor transducer

25201 Axis C1 drive fault

Another strange detail that after reset error if I move spindlle motor by hand same fault apiers. Seems that system still following encoders or something.

Maybe someone can help? Thanks

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Split from Why need to change MD 30240 to 0.?.

Have solved problem with active encoder adjusted gap between scaning head and magnetic dist. But not sure why getting passive encoder fault.

Now have these faults:

25001 Axis C1 hardware fault of passive encoder

300504 Axis C1 drive 3 fault of motor transducer

25201 Axis C1 drive fault

Have tested passive encoder (Heidenhain ERN 1381) with oscilo and get these rezults maybe someone can explain because voltage seems too hight??