diff --git a/app/HGProductionTool/dialog_inputserialnum.cpp b/app/HGProductionTool/dialog_inputserialnum.cpp
index 16e3239..cb0781e 100644
--- a/app/HGProductionTool/dialog_inputserialnum.cpp
+++ b/app/HGProductionTool/dialog_inputserialnum.cpp
@@ -177,7 +177,7 @@ void Dialog_InputSerialNum::setDevceModel()
     SANE_Status ret = sane_io_control(m_handle, IO_CTRL_CODE_SET_DEVS_MODEL, &deviceModel[0], &len);
 
     QString info("");
-    if (ret = SANE_STATUS_GOOD)
+    if (ret == SANE_STATUS_GOOD)
     {
         info = tr("Set") + tr("Device model: %1").arg(QString::fromStdString(deviceModel));
     }