diff --git a/AsbCloudInfrastructure/Services/Subsystems/SubsystemOperationTimeService.cs b/AsbCloudInfrastructure/Services/Subsystems/SubsystemOperationTimeService.cs
index 22de29ac..150970f2 100644
--- a/AsbCloudInfrastructure/Services/Subsystems/SubsystemOperationTimeService.cs
+++ b/AsbCloudInfrastructure/Services/Subsystems/SubsystemOperationTimeService.cs
@@ -65,9 +65,11 @@ namespace AsbCloudInfrastructure.Services.Subsystems
                 if (!request.LtDate.HasValue)
                     throw new ArgumentNullException(nameof(request.LtDate));
                 var end = request.LtDate.Value.ToUtcDateTimeOffset(well.Timezone.Hours);
-                var data = query.ToList();
+                IEnumerable<SubsystemOperationTime>? data = query.ToList();
                 data = Trim(data, begin, end);
-                return data.Select(o => Convert(o, well));
+                if (data is not null)
+                    return data.Select(o => Convert(o, well));
+                return null;
             }
             var dtos = query.Select(o => Convert(o, well));
             return dtos;
@@ -81,23 +83,23 @@ namespace AsbCloudInfrastructure.Services.Subsystems
             var statList = CalcStat(data, request);
             return statList;
         }
-        private List<SubsystemOperationTime> Trim(List<SubsystemOperationTime> data, DateTimeOffset gtDate, DateTimeOffset ltDate)
+        private IEnumerable<SubsystemOperationTime>? Trim(IEnumerable<SubsystemOperationTime>? data, DateTimeOffset gtDate, DateTimeOffset ltDate)
         {
+            if (data is null)
+                return null;
             var ItemsNormal = data.Where(q =>
             (q.DateStart >= gtDate) && (q.DateEnd <= ltDate)).ToList();
             var itemsToTrim = data.Where(q =>
-            (q.DateStart < gtDate && q.DateEnd <= ltDate && q.DateEnd > gtDate) ||
-            (q.DateStart >= gtDate && q.DateEnd > ltDate && q.DateStart < ltDate) ||
-            (q.DateStart < gtDate && q.DateEnd > ltDate))
+                q.DateStart < gtDate ||  ltDate < q.DateEnd)
                 .Select(o => new SubsystemOperationTime
                 {
-                    Id = o.Id,
-                    DateStart = (o.DateStart >= gtDate) && (o.DateStart <= ltDate) ? o.DateStart : gtDate,
-                    DateEnd = (o.DateEnd >= gtDate) && (o.DateEnd <= ltDate) ? o.DateEnd : ltDate,                    
+                    Id = o.Id,                    
+                    DateStart = gtDate < o.DateStart ? o.DateStart : gtDate,
+                    DateEnd = ltDate > o.DateEnd ? o.DateEnd : ltDate,                    
                     IdSubsystem = o.IdSubsystem,
-                    IdTelemetry = o.IdTelemetry,
-                    DepthEnd = (o.DateEnd >= gtDate) && (o.DateEnd <= ltDate) ? o.DepthEnd : null ,
-                    DepthStart = (o.DateStart >= gtDate) && (o.DateStart <= ltDate) ? o.DepthStart : null,
+                    IdTelemetry = o.IdTelemetry,                    
+                    DepthStart = gtDate > o.DateEnd ? o.DepthStart : null,
+                    DepthEnd = ltDate < o.DateStart ? o.DepthEnd : null,
                     Subsystem = o.Subsystem,
                     Telemetry = o.Telemetry
                 })
@@ -140,21 +142,34 @@ namespace AsbCloudInfrastructure.Services.Subsystems
             var query = db.SubsystemOperationTimes
             .Include(o => o.Subsystem)
             .Where(o => o.IdTelemetry == well.IdTelemetry);
-            
-            if(request.IdsSubsystems?.Any() == true)
+            DateTimeOffset gtDateWellTime;
+            DateTimeOffset ltDateWellTime;
+            if (request.IdsSubsystems?.Any() == true)
                 query = query.Where(o => request.IdsSubsystems.Contains(o.IdSubsystem));
 
-
             if (request.GtDate is not null && request.LtDate is not null)
             {
-                query = query.Where(o => (o.DateStart >= request.GtDate.Value.ToUtcDateTimeOffset(well.Timezone.Hours))
-                ||(o.DateEnd <= request.LtDate.Value.ToUtcDateTimeOffset(well.Timezone.Hours)));
+                gtDateWellTime = request.GtDate.Value.ToUtcDateTimeOffset(well.Timezone.Hours);
+                ltDateWellTime = request.LtDate.Value.ToUtcDateTimeOffset(well.Timezone.Hours);
+                //query = query.Where(o => (o.DateStart >= gtDateWellTime)
+                //|| (o.DateEnd <= ltDateWellTime));
+                query = query.Where(q =>
+                    (q.DateStart < gtDateWellTime && q.DateEnd <= ltDateWellTime && q.DateEnd > gtDateWellTime) ||
+            (q.DateStart >= gtDateWellTime && q.DateEnd > ltDateWellTime && q.DateStart < ltDateWellTime) ||
+            (q.DateStart < gtDateWellTime && q.DateEnd > ltDateWellTime) ||
+            (q.DateStart >= gtDateWellTime && q.DateEnd <= ltDateWellTime));
+            }
+            else if (request.GtDate is not null)
+            {
+                gtDateWellTime = request.GtDate.Value.ToUtcDateTimeOffset(well.Timezone.Hours);
+                query = query.Where(o => o.DateStart >= gtDateWellTime);
             }
-            else if (request.GtDate is not null)            
-                query = query.Where(o => o.DateStart >= request.GtDate.Value.ToUtcDateTimeOffset(well.Timezone.Hours));
 
             else if (request.LtDate is not null)
-                query = query.Where(o => o.DateEnd <= request.LtDate.Value.ToUtcDateTimeOffset(well.Timezone.Hours));
+            {
+                ltDateWellTime = request.LtDate.Value.ToUtcDateTimeOffset(well.Timezone.Hours);
+                query = query.Where(o => o.DateEnd <= ltDateWellTime);
+            }
            
             
             if (request.GtDepth is not null)