diff --git a/ats/verify/simulation/wayside/memory/wayside_memory_map.go b/ats/verify/simulation/wayside/memory/wayside_memory_map.go
index 05e30b0..2ead4a0 100644
--- a/ats/verify/simulation/wayside/memory/wayside_memory_map.go
+++ b/ats/verify/simulation/wayside/memory/wayside_memory_map.go
@@ -131,10 +131,10 @@ func sectionMapToEcsLink(repo *repository.Repository, id string, status *state.T
 	if section == nil {
 		panic(sys_error.New(fmt.Sprintf("地图不存在uid:%s缓存", id)))
 	}
-	link := section.ALinkPosition().Link()
-	// 检查link偏移
-	status.HeadOffset = checkOffsetInLink(status.HeadOffset, status.TrainLength, link)
 	ao, bo := section.ALinkPosition().Offset(), section.BLinkPosition().Offset()
+	// 检查区段长度是否足够放下列车
+	status.HeadOffset = checkDeviceContainTrain(status.HeadOffset, status.TrainLength, bo-ao)
+	link := section.ALinkPosition().Link()
 	// 是否从A到B，统一坐标
 	ak, bk := convertRepoBaseKm(repo, section.AKilometer()), convertRepoBaseKm(repo, section.BKilometer())
 	akv, bkv := ak.Value, bk.Value
@@ -186,16 +186,16 @@ func turnoutMapToEcsLink(repo *repository.Repository, id string, status *state.T
 	default:
 		panic(sys_error.New(fmt.Sprintf("无效端口【%s】偏移量", port)))
 	}
-	// 关联link
-	link := portPosition.Link()
-	// 检查link偏移
-	status.HeadOffset = checkOffsetInLink(status.HeadOffset, status.TrainLength, link)
 	// 岔心公里标
 	crossKm = turnout.GetTurnoutKm(proto2.Port_None)
 	portKm, err := repo.ConvertKilometer(portKm, crossKm.CoordinateSystem)
 	if err != nil {
 		panic(sys_error.New("公里标转换出错", err))
 	}
+	// 检查link偏移
+	status.HeadOffset = checkDeviceContainTrain(status.HeadOffset, status.TrainLength, crossKm.Value-portKm.Value)
+	// 关联link
+	link := portPosition.Link()
 	isStart := link.ARelation().Device().Id() == id
 	up := runDirection
 	if (portKm.Value > crossKm.Value) != isStart {
@@ -366,16 +366,17 @@ func convertRepoBaseKm(r *repository.Repository, km *proto2.Kilometer) *proto2.K
 	return k
 }
 
-// 检查偏移是否在link上,返回最终的offset
-func checkOffsetInLink(offset, trainLen int64, link *repository.Link) int64 {
-	if offset > link.Length() {
-		panic(sys_error.New(fmt.Sprintf("偏移【%d】超出link范围【%d】", offset, link.Length())))
+// 检查列车是否可以放到设备上
+func checkDeviceContainTrain(offset, trainLen, deviceLen int64) int64 {
+	l := int64(math.Abs(float64(deviceLen)))
+	if offset > l {
+		panic(sys_error.New(fmt.Sprintf("偏移【%d】超出设备范围【%d】", offset, l)))
 	}
 	if trainLen > offset { // 如果列车长度超过设置offset
 		offset = trainLen
 	}
-	if offset > link.Length() {
-		panic(sys_error.New(fmt.Sprintf("列车长度【%d】超出link范围【%d】", trainLen, link.Length())))
+	if offset > l {
+		panic(sys_error.New(fmt.Sprintf("列车长度【%d】超出设备范围【%d】", trainLen, l)))
 	}
 	return offset
 }