983T-H zero return problem

Dear CNCMAKERS Officer,
Have a nice day!
I Have problem with the 983T-H CNC Lathe Controller. could you explain this?
( http://www.cncmakers.com/cnc/controllers/CNC_Controllers_for_Lathes/GSK983T.html )
( http://www.cncmakers.com/cnc/controllers/CNC_Controllers_for_Lathes/GSK983T.html )
I can't get "constant position" performed with "zero return" operation.
setting-A
Parameter-0012 : reference return using "grid switch"
the result is change about 2mm, when "zero return position start" (position when I press zero return x/z button) change 10mm.
and increment. until the result change 10mm when "zero return position start" change 50mm.
setting-A
Parameter-0012 : reference return using "grid switch"
the result is change about 2mm, when "zero return position start" (position when I press zero return x/z button) change 10mm.
and increment. until the result change 10mm when "zero return position start" change 50mm.
I have tray some option with parameter 0082, 0083, 0092, 0093, 0114 but no effect.
when "zero return position start" not change (not moved). the result get constant,
Setting-B
Parameter-0012 : reference return using "magnet switch"
can't performed, due no ZDX, ZDZ signal available.
Parameter-0012 : reference return using "magnet switch"
can't performed, due no ZDX, ZDZ signal available.
Thanks for prompt replay..
The problem SOLVED for now, I change "The Backlash initial direction" Parameter 0012.