diff --git a/LFP_Manager/DataStructure/csDataStructure.cs b/LFP_Manager/DataStructure/csDataStructure.cs
index b166057..b0a3ce7 100644
--- a/LFP_Manager/DataStructure/csDataStructure.cs
+++ b/LFP_Manager/DataStructure/csDataStructure.cs
@@ -23,7 +23,7 @@ namespace LFP_Manager.DataStructure
         public int UartModelIndex;
         public int UartProtocol;
 
-        public int CommFailTime;
+        public int CommFailMaxCount;
 
         public int DbLogPeriod;
 
@@ -49,7 +49,7 @@ namespace LFP_Manager.DataStructure
             UartProtocol = 0;
 
             RecvWaitTime = 1500;    // 1500ms
-            CommFailTime = 5000;    // 5000ms
+            CommFailMaxCount = 5;   // 5 times
 
             DbLogPeriod = 5;
 
diff --git a/LFP_Manager/Function/csIniControlFunction.cs b/LFP_Manager/Function/csIniControlFunction.cs
index 60914bb..470129b 100644
--- a/LFP_Manager/Function/csIniControlFunction.cs
+++ b/LFP_Manager/Function/csIniControlFunction.cs
@@ -106,7 +106,7 @@ namespace LFP_Manager.Function
                 rConfig.RecvWaitTime = (int)csIniControlFunction.GetPrivateProfileInt("UART", "RECV_WAIT_TIME", 1500, InIPath);
 
                 // COMM FAIL TIME OUT
-                rConfig.CommFailTime = (int)csIniControlFunction.GetPrivateProfileInt("UART", "COMM_FAIL_TIME", 5000, InIPath);
+                rConfig.CommFailMaxCount = (int)csIniControlFunction.GetPrivateProfileInt("UART", "COMM_FAIL_COUNT", 5, InIPath);
 
                 // Etc. Config
                 rConfig.DbLogPeriod = (int)csIniControlFunction.GetPrivateProfileInt("DATABASE", "LOG_PERIOD", 1, InIPath);
@@ -147,7 +147,7 @@ namespace LFP_Manager.Function
                 rConfig.UartProtocol= 0;
                 rConfig.RecvWaitTime = 1500;
 
-                rConfig.CommFailTime = 5000;
+                rConfig.CommFailMaxCount = 5;
 
                 rConfig.DbLogPeriod = 5;
 
@@ -187,8 +187,8 @@ namespace LFP_Manager.Function
             // RECV_WAIT_TIME
             WritePrivateProfileString("UART", "RECV_WAIT_TIME", aConfig.RecvWaitTime.ToString(), InIPath);
 
-            // COMM_FAIL_TIME
-            WritePrivateProfileString("UART", "COMM_FAIL_TIME", aConfig.CommFailTime.ToString(), InIPath);
+            // COMM_FAIL_COUNT
+            WritePrivateProfileString("UART", "COMM_FAIL_COUNT", aConfig.CommFailMaxCount.ToString(), InIPath);
 
             // Etc Config
             WritePrivateProfileString("DATABASE", "LOG_PERIOD", aConfig.DbLogPeriod.ToString(), InIPath);
diff --git a/LFP_Manager/Threads/CsUartThreadSB.cs b/LFP_Manager/Threads/CsUartThreadSB.cs
index 28a063a..7fa93bf 100644
--- a/LFP_Manager/Threads/CsUartThreadSB.cs
+++ b/LFP_Manager/Threads/CsUartThreadSB.cs
@@ -463,8 +463,9 @@ namespace LFP_Manager.Threads
         private void uartCommThreadSB(CancellationToken token)
         {
             int RecvTimeout = Config.RecvWaitTime;
-            int COMM_TIMEOUT_MS = Config.CommFailTime;   // 5초 동안 수신 없으면 Fail
+            int COMM_TIMEOUT_MAX_COUNT = (Config.CommFailMaxCount > 100) ? 5 : Config.CommFailMaxCount;   // 5초 동안 수신 없으면 Fail
             DateTime[] LastReceiveTime = new DateTime[csConstData.SystemInfo.MAX_MODULE_SIZE];
+            int[] RecvTimeoutCount = new int[csConstData.SystemInfo.MAX_MODULE_SIZE];
 
             // ★ 마지막 수신 시간 초기화 (현재 시각 기준)
             var now = DateTime.UtcNow;
@@ -532,8 +533,9 @@ namespace LFP_Manager.Threads
                                 {
                                     // 마지막 정상 업데이트 시간 기록
                                     LastReceiveTime[mID] = DateTime.UtcNow;
+                                    RecvTimeoutCount[mID] = 0;
 
-                                    ModuleData[mID].CommFail = false;
+                                    ModuleData[mID].mNo = mID + 1;
                                     ModuleData[mID].ShelfCommFail = false;
                                     var rc = CsSerialCommFunctionDelta.SerialRxProcess(
                                                 ReadBuf, RequestRegAddr, (ushort)rPosition, ref ModuleData[mID]);
@@ -576,25 +578,26 @@ namespace LFP_Manager.Threads
                     {
                         int idx = csUtils.MathEx.Clamp(ModuleID - 1, 0, csConstData.SystemInfo.MAX_MODULE_SIZE - 1);
 
+                        RecvTimeoutCount[idx]++;
                         // 아직 한 번도 정상 수신한 적 없는 경우 MinValue일 수 있으므로,
                         // 첫 타임아웃에서는 기준 시간을 현재로 초기화해 준다.
                         if (LastReceiveTime[idx] == DateTime.MinValue)
                             LastReceiveTime[idx] = DateTime.UtcNow;
 
                         // 시간 차이 계산
-                        var elapsed = (DateTime.Now - LastReceiveTime[idx]).TotalMilliseconds;
+                        var elapsed = (DateTime.UtcNow - LastReceiveTime[idx]).TotalMilliseconds;
 
-                        if (elapsed >= COMM_TIMEOUT_MS)
+                        if (RecvTimeoutCount[idx] >= COMM_TIMEOUT_MAX_COUNT)
+                        //if (elapsed >= COMM_TIMEOUT_MS)
                         {
+                            RecvTimeoutCount[idx] = 5;
                             // Fail 처리
                             if (!ModuleData[idx].ShelfCommFail)
                             {
                                 ModuleData[idx].Reset();
+                                ModuleData[idx].mNo = ModuleID;
                                 ModuleData[idx].ShelfCommFail = true;
                             }
-
-                            ModuleData[idx].CommFail = true;
-                            ModuleData[idx].ShelfCommFail = true;
                         }
                         Thread.Sleep(100);
                     }
diff --git a/LFP_Manager/Threads/csDbThread.cs b/LFP_Manager/Threads/csDbThread.cs
index 8b5c859..3681b97 100644
--- a/LFP_Manager/Threads/csDbThread.cs
+++ b/LFP_Manager/Threads/csDbThread.cs
@@ -492,11 +492,11 @@ namespace LFP_Manager.Threads
             DateTime now = DateTime.Now;
 
             // 시스템 통신 상태 변화 기록
-            if (oModule.CommFail != nModule.CommFail)
+            if (oModule.ShelfCommFail != nModule.ShelfCommFail)
             {
                 eventFlag |= BmsAlarmDataInsert(modelName, (int)DbConstData.Alarm.COMM_FAIL,
-                    nModule.CommFail ? (int)DbConstData.Flag.WARNING : (int)DbConstData.Flag.RELEASE, nModule, now);
-                oModule.CommFail = nModule.CommFail;
+                    nModule.ShelfCommFail ? (int)DbConstData.Flag.WARNING : (int)DbConstData.Flag.RELEASE, nModule, now);
+                oModule.ShelfCommFail = nModule.ShelfCommFail;
             }
             // 0..15 비트에 대한 경고/보호 엣지 검사
             for (int i = 0; i < 16; i++)