diff --git a/acs2/nladmin-system/nlsso-server/src/main/java/org/nl/acs/device_driver/conveyor/belt_conveyor/BeltConveyorDeviceDriver.java b/acs2/nladmin-system/nlsso-server/src/main/java/org/nl/acs/device_driver/conveyor/belt_conveyor/BeltConveyorDeviceDriver.java
index f8a401698..6b2798d44 100644
--- a/acs2/nladmin-system/nlsso-server/src/main/java/org/nl/acs/device_driver/conveyor/belt_conveyor/BeltConveyorDeviceDriver.java
+++ b/acs2/nladmin-system/nlsso-server/src/main/java/org/nl/acs/device_driver/conveyor/belt_conveyor/BeltConveyorDeviceDriver.java
@@ -558,11 +558,11 @@ public class BeltConveyorDeviceDriver extends AbstractOpcDeviceDriver implements
 
                 //入库异常口为起点的任务
                 TaskDto taskdto = taskserver.findByStartCodeAndReady(device_code);
-                //移除行架任务
-                if (taskdto.getTask_type().equals(TaskTypeEnum.Truss_Task.getIndex())){
-                    return false;
-                }
                 if (ObjectUtil.isNotNull(taskdto)) {
+                    //移除行架任务
+                    if (taskdto.getTask_type().equals(TaskTypeEnum.Truss_Task.getIndex())){
+                        return false;
+                    }
                     //判断指令的起点和当前的设备号相同
                     if (!taskdto.getStart_device_code().equals(device_code)) {
                         return false;
diff --git a/acs2/nladmin-system/nlsso-server/src/main/java/org/nl/acs/device_driver/stacker/standard_stacker/ItemProtocol.java b/acs2/nladmin-system/nlsso-server/src/main/java/org/nl/acs/device_driver/stacker/standard_stacker/ItemProtocol.java
index f007d5555..2ab327c17 100644
--- a/acs2/nladmin-system/nlsso-server/src/main/java/org/nl/acs/device_driver/stacker/standard_stacker/ItemProtocol.java
+++ b/acs2/nladmin-system/nlsso-server/src/main/java/org/nl/acs/device_driver/stacker/standard_stacker/ItemProtocol.java
@@ -273,14 +273,14 @@ public class ItemProtocol {
             setIsonline(true);
             return value;
         }
-        return value;
+        return 0;
     }
 
     public String getOpcStringValue(String protocol) {
         String value = this.driver.getStringValue(protocol);
         if (value == null) {
             setIsonline(false);
-            return value;
+            return "";
         } else {
             setIsonline(true);
             return value;