diff --git a/fusion_iot/fusion_plating_iot/__manifest__.py b/fusion_iot/fusion_plating_iot/__manifest__.py
index 929ef302..a1bb846a 100644
--- a/fusion_iot/fusion_plating_iot/__manifest__.py
+++ b/fusion_iot/fusion_plating_iot/__manifest__.py
@@ -5,7 +5,7 @@
 
 {
     'name': 'Fusion Plating — IoT Integration',
-    'version': '19.0.0.2.0',
+    'version': '19.0.0.3.0',
     'category': 'Manufacturing/Plating',
     'summary': 'Wire physical tank sensors to Fusion Plating — live '
                'temperature / chemistry readings with auto quality holds '
diff --git a/fusion_iot/fusion_plating_iot/models/fp_tank_reading.py b/fusion_iot/fusion_plating_iot/models/fp_tank_reading.py
index 0035eb8e..8d982d3f 100644
--- a/fusion_iot/fusion_plating_iot/models/fp_tank_reading.py
+++ b/fusion_iot/fusion_plating_iot/models/fp_tank_reading.py
@@ -95,6 +95,66 @@ class FpTankReading(models.Model):
                 r.display_value = r.value
                 r.display_unit = r.parameter_id.uom or ''
 
+    # ------------------------------------------------------------------
+    # Deviation from setpoint — signed Δ from the sensor's effective target
+    # in the company-preferred unit. Zero if no setpoint defined.
+    # ------------------------------------------------------------------
+    deviation_from_target = fields.Float(
+        string='Δ from Setpoint',
+        compute='_compute_deviation',
+        digits=(12, 2),
+        help='Signed difference between this reading and the sensor\'s '
+             'setpoint, in the company-preferred unit. Positive = above '
+             'setpoint, negative = below. Zero if no setpoint is defined.',
+    )
+    deviation_band = fields.Selection(
+        [
+            ('none',   'No setpoint'),
+            ('on',     'On target (±1°)'),
+            ('near',   'Near target (±3°)'),
+            ('far',    'Far from target (>3°)'),
+            ('out',    'Out of spec'),
+        ],
+        string='Band',
+        compute='_compute_deviation',
+        help='Coarse band for quick visual scanning in lists.',
+    )
+
+    @api.depends('value', 'display_value', 'in_spec',
+                 'sensor_id', 'sensor_id.target_value_override',
+                 'sensor_id.parameter_id.target_value',
+                 'sensor_id.parameter_id.parameter_type')
+    def _compute_deviation(self):
+        pref = self.env.company.x_fc_default_temp_uom or 'C'
+        for r in self:
+            sensor = r.sensor_id
+            if not sensor:
+                r.deviation_from_target = 0.0
+                r.deviation_band = 'none'
+                continue
+            raw_sp = sensor._get_setpoint()
+            if not raw_sp:
+                r.deviation_from_target = 0.0
+                r.deviation_band = 'none'
+                continue
+            # Convert setpoint + value to display unit for the delta so the
+            # number shown matches what operators expect (°F if pref=F).
+            ptype = (sensor.parameter_id.parameter_type or '').lower()
+            if ptype == 'temperature' and pref == 'F':
+                sp_disp = raw_sp * 9.0 / 5.0 + 32.0
+            else:
+                sp_disp = raw_sp
+            delta = r.display_value - sp_disp
+            r.deviation_from_target = round(delta, 2)
+            if not r.in_spec:
+                r.deviation_band = 'out'
+            elif abs(delta) <= 1.0:
+                r.deviation_band = 'on'
+            elif abs(delta) <= 3.0:
+                r.deviation_band = 'near'
+            else:
+                r.deviation_band = 'far'
+
     source = fields.Selection(
         [
             ('iot_proxy', 'IoT Proxy (Pi)'),
diff --git a/fusion_iot/fusion_plating_iot/models/fp_tank_sensor.py b/fusion_iot/fusion_plating_iot/models/fp_tank_sensor.py
index ee734cc7..c0004daf 100644
--- a/fusion_iot/fusion_plating_iot/models/fp_tank_sensor.py
+++ b/fusion_iot/fusion_plating_iot/models/fp_tank_sensor.py
@@ -76,12 +76,24 @@ class FpTankSensor(models.Model):
     )
 
     # ------------------------------------------------------------------
-    # Alerting behaviour
+    # Target / alerting behaviour — three concepts:
+    #   setpoint  → what we CONTROL TOWARD (dashboards, PID, trend baseline)
+    #   alert min → lower alarm boundary (quality hold fires below)
+    #   alert max → upper alarm boundary (quality hold fires above)
+    #
+    # All three have a parameter-level default + per-sensor override
+    # pattern so users can fine-tune per-tank without touching the
+    # shop-wide spec. Zero on an override field = "inherit from parameter".
     # ------------------------------------------------------------------
+    target_value_override = fields.Float(
+        string='Setpoint / Optimum (override)', digits=(10, 4),
+        help='Optional per-sensor override of the parameter\'s default '
+             'setpoint. Leave 0 to inherit from bath.parameter.target_value.',
+    )
     alert_on_out_of_spec = fields.Boolean(
         string='Alert on Out-of-Spec', default=True,
         help='If checked, a fusion.plating.quality.hold is auto-created '
-             'when a reading falls outside the parameter target range.',
+             'when a reading falls outside the alert_min/alert_max band.',
     )
     alert_min_override = fields.Float(
         string='Alert Min (override)', digits=(10, 4),
@@ -94,6 +106,37 @@ class FpTankSensor(models.Model):
              'specific sensor.',
     )
 
+    # ------------------------------------------------------------------
+    # Effective target — resolves override → parameter default → 0
+    # ------------------------------------------------------------------
+    effective_target = fields.Float(
+        string='Effective Setpoint',
+        compute='_compute_effective_target',
+        digits=(12, 2),
+        help='The setpoint currently in use, after applying any per-sensor '
+             'override. Displayed in the company-preferred unit.',
+    )
+    effective_target_unit = fields.Char(
+        string='Setpoint Unit',
+        compute='_compute_effective_target',
+    )
+
+    @api.depends('target_value_override', 'parameter_id.target_value',
+                 'parameter_id.parameter_type', 'parameter_id.uom')
+    def _compute_effective_target(self):
+        pref = self.env.company.x_fc_default_temp_uom or 'C'
+        for rec in self:
+            raw = rec.target_value_override or (
+                rec.parameter_id.target_value if rec.parameter_id else 0.0
+            )
+            ptype = (rec.parameter_id.parameter_type or '').lower()
+            if ptype == 'temperature' and pref == 'F':
+                rec.effective_target = raw * 9.0 / 5.0 + 32.0 if raw else 0.0
+                rec.effective_target_unit = '°F'
+            else:
+                rec.effective_target = raw
+                rec.effective_target_unit = rec.parameter_id.uom or ''
+
     # ------------------------------------------------------------------
     # Cached latest-reading fields (for quick display in list views)
     # ------------------------------------------------------------------
@@ -163,6 +206,17 @@ class FpTankSensor(models.Model):
         )
         return (lo or 0.0, hi or 0.0)
 
+    def _get_setpoint(self):
+        """Canonical (raw) setpoint used for deviation calcs.
+
+        Returns 0.0 if no setpoint is set at either level — callers should
+        treat 0 as "no target defined, skip deviation display".
+        """
+        self.ensure_one()
+        return self.target_value_override or (
+            self.parameter_id.target_value if self.parameter_id else 0.0
+        ) or 0.0
+
     def action_view_readings(self):
         self.ensure_one()
         return {
diff --git a/fusion_iot/fusion_plating_iot/views/fp_tank_reading_views.xml b/fusion_iot/fusion_plating_iot/views/fp_tank_reading_views.xml
index e2023b95..48fc1de6 100644
--- a/fusion_iot/fusion_plating_iot/views/fp_tank_reading_views.xml
+++ b/fusion_iot/fusion_plating_iot/views/fp_tank_reading_views.xml
@@ -10,15 +10,22 @@
         <field name="model">fp.tank.reading</field>
         <field name="arch" type="xml">
             <list string="Sensor Readings"
-                  decoration-danger="not in_spec" default_order="reading_at desc">
+                  default_order="reading_at desc"
+                  decoration-danger="deviation_band == 'out'"
+                  decoration-warning="deviation_band == 'far'"
+                  decoration-info="deviation_band == 'near'"
+                  decoration-success="deviation_band == 'on'"
+                  decoration-muted="deviation_band == 'none'">
                 <field name="reading_at"/>
                 <field name="sensor_id"/>
                 <field name="tank_id" optional="show"/>
                 <field name="parameter_id" optional="hide"/>
                 <field name="display_value"/>
                 <field name="display_unit"/>
+                <field name="deviation_from_target"/>
+                <field name="deviation_band" widget="badge"/>
                 <field name="value" optional="hide" string="Value (°C raw)"/>
-                <field name="in_spec" widget="boolean_toggle"/>
+                <field name="in_spec" widget="boolean_toggle" optional="show"/>
                 <field name="source" optional="hide"/>
                 <field name="hold_id" optional="show"/>
             </list>
diff --git a/fusion_iot/fusion_plating_iot/views/fp_tank_sensor_views.xml b/fusion_iot/fusion_plating_iot/views/fp_tank_sensor_views.xml
index fe03d2ac..249bab91 100644
--- a/fusion_iot/fusion_plating_iot/views/fp_tank_sensor_views.xml
+++ b/fusion_iot/fusion_plating_iot/views/fp_tank_sensor_views.xml
@@ -69,13 +69,19 @@
                             <field name="parameter_id" options="{'no_create': True}"/>
                         </group>
                     </group>
-                    <group string="Alerting">
-                        <group>
+                    <group string="Setpoint &amp; Alerting">
+                        <group string="Target (setpoint)">
+                            <field name="target_value_override"
+                                   help="Leave 0 to inherit from bath parameter's Default Setpoint. This is the IDEAL operating value — not an alarm threshold."/>
+                            <field name="effective_target" readonly="1"/>
+                            <field name="effective_target_unit" readonly="1"/>
+                        </group>
+                        <group string="Alarm band">
                             <field name="alert_on_out_of_spec"/>
                             <field name="alert_min_override"
-                                   help="Leave 0 to inherit from the bath parameter's target_min."/>
+                                   help="Leave 0 to inherit from the bath parameter's target_min. Readings below this fire a quality hold."/>
                             <field name="alert_max_override"
-                                   help="Leave 0 to inherit from the bath parameter's target_max."/>
+                                   help="Leave 0 to inherit from the bath parameter's target_max. Readings above this fire a quality hold."/>
                         </group>
                         <group string="Most Recent Reading">
                             <field name="last_reading_display" readonly="1"/>
diff --git a/fusion_iot/fusion_plating_iot/views/fusion_plating_tank_views.xml b/fusion_iot/fusion_plating_iot/views/fusion_plating_tank_views.xml
index d9a0c04c..6ea521a2 100644
--- a/fusion_iot/fusion_plating_iot/views/fusion_plating_tank_views.xml
+++ b/fusion_iot/fusion_plating_iot/views/fusion_plating_tank_views.xml
@@ -24,6 +24,8 @@
                                 <field name="device_kind"/>
                                 <field name="device_serial"/>
                                 <field name="parameter_id"/>
+                                <field name="effective_target" readonly="1"/>
+                                <field name="effective_target_unit" readonly="1"/>
                                 <field name="last_reading_display"/>
                                 <field name="last_reading_display_unit"/>
                                 <field name="last_reading_at" readonly="1"/>
diff --git a/fusion_plating/fusion_plating/__manifest__.py b/fusion_plating/fusion_plating/__manifest__.py
index b37c9437..a301d85e 100644
--- a/fusion_plating/fusion_plating/__manifest__.py
+++ b/fusion_plating/fusion_plating/__manifest__.py
@@ -5,7 +5,7 @@
 
 {
     'name': 'Fusion Plating',
-    'version': '19.0.5.4.0',
+    'version': '19.0.5.5.0',
     'category': 'Manufacturing/Plating',
     'summary': 'Core plating / metal finishing ERP: facilities, processes, tanks, baths, jobs, operators.',
     'description': """
diff --git a/fusion_plating/fusion_plating/models/fp_bath_parameter.py b/fusion_plating/fusion_plating/models/fp_bath_parameter.py
index 3e980d28..0f6b618f 100644
--- a/fusion_plating/fusion_plating/models/fp_bath_parameter.py
+++ b/fusion_plating/fusion_plating/models/fp_bath_parameter.py
@@ -61,6 +61,13 @@ class FpBathParameter(models.Model):
         string='Default Target Max',
         help='Default target maximum. Per-bath overrides are allowed.',
     )
+    target_value = fields.Float(
+        string='Default Setpoint / Optimum',
+        help='The IDEAL operating value — what the heater/chiller controls '
+             'toward, what dashboards compare against. Sits between '
+             'target_min and target_max. Per-sensor override via '
+             'fp.tank.sensor.target_value_override.',
+    )
     warning_tolerance = fields.Float(
         string='Warning Tolerance %',
         default=10.0,