diff --git a/modules/lot/lot.py b/modules/lot/lot.py
index 606bce4..69ae16f 100755
--- a/modules/lot/lot.py
+++ b/modules/lot/lot.py
@@ -500,7 +500,12 @@ class Lot(ModelSQL, ModelView):
                 physic_sum = Decimal(0)
                 for l in line.lots:
                     if l.lot_type == 'physic' :
-                        physic_sum += round(Decimal(Uom.compute_qty(Uom(l.lot_unit_line),float(l.get_current_quantity()),l.line.unit, True, 1, 1)),5)
+                        factor = None
+                        rate = None
+                        if l.lot_unit_line.category.id != l.line.unit.category.id:
+                            factor = 1
+                            rate = 1
+                        physic_sum += round(Decimal(Uom.compute_qty(Uom(l.lot_unit_line),float(l.get_current_quantity()),l.line.unit, True, factor, rate)),5)
                 return line.quantity_theorical - physic_sum
 
     def get_current_quantity(self,name=None):
@@ -515,14 +520,24 @@ class Lot(ModelSQL, ModelView):
         if not unit:
             unit = self.line.unit if self.line else self.sale_line.unit
         qt, gross_qt = self.get_hist_quantity(state_id)
-        return round(Decimal(Uom.compute_qty(self.lot_unit_line, float(qt), unit, True, 1, 1)),5)
+        factor = None
+        rate = None
+        if self.lot_unit_line.category.id != unit.category.id:
+            factor = 1
+            rate = 1
+        return round(Decimal(Uom.compute_qty(self.lot_unit_line, float(qt), unit, True, factor, rate)),5)
     
     def get_current_gross_quantity_converted(self,state_id=0,unit=None):
         Uom = Pool().get('product.uom')
         if not unit:
             unit = self.line.unit if self.line else self.sale_line.unit
         qt, gross_qt = self.get_hist_quantity(state_id)
-        return round(Decimal(Uom.compute_qty(self.lot_unit_line, float(gross_qt), unit, True, 1, 1)),5)
+        factor = None
+        rate = None
+        if self.lot_unit_line.category.id != unit.category.id:
+            factor = 1
+            rate = 1
+        return round(Decimal(Uom.compute_qty(self.lot_unit_line, float(gross_qt), unit, True, factor, rate)),5)
         
     def get_current_gross_quantity(self,name=None):
         if self.lot_type == 'physic':