@@ -609,7 +609,11 @@ def execute_plan(self):
                         else:
                             # If there is a previous set charge window, but its more than the set window minutes in the future but we are not close to it then we can leave it enabled for now
                             # saves register writes and avoids turning off the window before the inverter knows it finished
-                            if (inverter.charge_start_time_minutes != inverter.charge_end_time_minutes) and (inverter.charge_start_time_minutes - self.minutes_now) > self.set_window_minutes:
+                            # Only for an inverter with no charge enable switch, where turning the charge off means rewriting the
+                            # window itself (#2993). With a switch it is one write that leaves the times alone, and leaving it on
+                            # arms every other slot the inverter has: on a GivEnergy 3-phase the unused slots, held at 00:00-00:00,
+                            # are live for the first minute of the day and charged from the grid at full rate (#5371)
+                            if (not inverter.inv_has_charge_enable_time) and (inverter.charge_start_time_minutes != inverter.charge_end_time_minutes) and (inverter.charge_start_time_minutes - self.minutes_now) > self.set_window_minutes:
                                 self.log(
                                     "Inverter {} leaving charge window as already set and more than set_window_minutes {} away (now {} charge start time {})".format(
                                         inverter.id, self.set_window_minutes, self.time_abs_str(self.minutes_now), self.time_abs_str(inverter.charge_start_time_minutes)
 
@@ -2394,18 +2394,52 @@ def run_execute_tests(my_predbat):
         inverter_charge_time_minutes_start=12 * 60,
         minutes_now=0,
     )
+    # The inverter still holds a window that finished, which now reads as tomorrow's, and the next planned
+    # charge is hours away. With a charge enable switch the switch goes off between windows: left on it arms
+    # every other slot the inverter has, and a GivEnergy 3-phase unit's unused 00:00-00:00 slots are live for
+    # the first minute of the day (#5371)
     failed |= run_execute_test(
         my_predbat,
         "charge_midnight2d",
         charge_window_best=charge_window_best7d,
         charge_limit_best=charge_limit_best,
+        assert_charge_time_enable=False,
+        set_charge_window=True,
+        set_export_window=True,
+        assert_status="Demand",
+        inverter_charge_time_minutes_start=30 + 24 * 60,
+    )
+    # With no switch, turning the charge off means rewriting the window, so it is left alone as before (#2993)
+    for inverter in my_predbat.inverters:
+        inverter.charge_time_enable = True
+    failed |= run_execute_test(
+        my_predbat,
+        "charge_midnight2d_no_enable_switch",
+        charge_window_best=charge_window_best7d,
+        charge_limit_best=charge_limit_best,
         assert_charge_time_enable=True,
         set_charge_window=True,
         set_export_window=True,
         assert_status="Demand",
         assert_charge_start_time_minutes=30 + 24 * 60,
         assert_charge_end_time_minutes=-1,
         inverter_charge_time_minutes_start=30 + 24 * 60,
+        has_charge_enable_time=False,
+    )
+    # And the switch comes back on once the next window is close enough to program
+    failed |= run_execute_test(
+        my_predbat,
+        "charge_midnight2d_window_close",
+        charge_window_best=charge_window_best7d,
+        charge_limit_best=charge_limit_best,
+        assert_charge_time_enable=True,
+        set_charge_window=True,
+        set_export_window=True,
+        assert_status="Demand",
+        assert_charge_start_time_minutes=22 * 60,
+        assert_charge_end_time_minutes=23 * 60,
+        inverter_charge_time_minutes_start=30 + 24 * 60,
+        minutes_now=22 * 60 - 10,
     )
 
     for inverter in my_predbat.inverters: