diff --git a/addons/mrp/models/mrp_production.py b/addons/mrp/models/mrp_production.py
index 98e2755e0e3..868c917f2ec 100644
--- a/addons/mrp/models/mrp_production.py
+++ b/addons/mrp/models/mrp_production.py
@@ -703,6 +703,8 @@ class MrpProduction(models.Model):
         self.ensure_one()
 
         # Schedule all work orders (new ones and those already created)
+        qty_to_produce = max(self.product_qty - self.qty_produced, 0)
+        qty_to_produce = self.product_uom_id._compute_quantity(qty_to_produce, self.product_id.uom_id)
         start_date = self._get_start_date()
         for workorder in self.workorder_ids:
             workcenters = workorder.workcenter_id | workorder.workcenter_id.alternative_workcenter_ids
@@ -712,7 +714,7 @@ class MrpProduction(models.Model):
             for workcenter in workcenters:
                 # compute theoretical duration
                 time_cycle = workorder.operation_id.time_cycle
-                cycle_number = float_round(workorder.qty_producing / workcenter.capacity, precision_digits=0, rounding_method='UP')
+                cycle_number = float_round(qty_to_produce / workcenter.capacity, precision_digits=0, rounding_method='UP')
                 duration_expected = workcenter.time_start + workcenter.time_stop + cycle_number * time_cycle * 100.0 / workcenter.time_efficiency
 
                 # get first free slot
@@ -740,7 +742,7 @@ class MrpProduction(models.Model):
 
             # Instantiate start_date for the next workorder planning
             if workorder.next_work_order_id:
-                if workorder.operation_id.batch == 'no' or workorder.operation_id.batch_size >= workorder.qty_producing:
+                if workorder.operation_id.batch == 'no' or workorder.operation_id.batch_size >= qty_to_produce:
                     start_date = best_finished_date
                 else:
                     cycle_number = float_round(workorder.operation_id.batch_size / best_workcenter.capacity, precision_digits=0, rounding_method='UP')
diff --git a/addons/mrp/tests/test_workorder_operation.py b/addons/mrp/tests/test_workorder_operation.py
index 3cccd8d167a..52b44901933 100644
--- a/addons/mrp/tests/test_workorder_operation.py
+++ b/addons/mrp/tests/test_workorder_operation.py
@@ -1263,6 +1263,26 @@ class TestWorkOrderProcess(TestWorkOrderProcessCommon):
         self.assertAlmostEqual(wo.date_planned_start, datetime.now(), delta=timedelta(seconds=10))
         self.assertAlmostEqual(wo.date_planned_finished, datetime.now(), delta=timedelta(seconds=10))
 
+    def test_planning_7(self):
+        """ set the workcenter capacity to 10. Produce a dozen of product tracked by
+        SN. The production should be done in two batches"""
+        self.workcenter_1.capacity = 10
+        self.workcenter_1.time_efficiency = 100
+        self.workcenter_1.time_start = 0
+        self.workcenter_1.time_stop = 0
+        self.routing_1.operation_ids.time_cycle = 60
+        self.product_4.tracking = 'serial'
+        mo_form = Form(self.env['mrp.production'])
+        mo_form.product_id = self.product_4
+        mo_form.bom_id = self.planning_bom
+        mo_form.product_uom_id = self.uom_dozen
+        mo_form.product_qty = 1
+        mo = mo_form.save()
+        mo.action_confirm()
+        mo.button_plan()
+        wo = mo.workorder_ids
+        self.assertEqual(wo.duration_expected, 120)
+
     def test_plan_unplan_date(self):
         """ Testing planning a workorder then cancel it and then plan it again.
         The planned date must be the same the first time and the second time the