diff --git a/src/PSUSensorMain.cpp b/src/PSUSensorMain.cpp
index 8a940b8..8c052a7 100644
--- a/src/PSUSensorMain.cpp
+++ b/src/PSUSensorMain.cpp
@@ -114,7 +114,7 @@
 static void checkPWMSensor(const fs::path& sensorPath, std::string& labelHead,
                            const std::string& interfacePath,
                            sdbusplus::asio::object_server& objectServer,
-                           std::string psuName)
+                           const std::string& psuName)
 {
     for (const auto& pwmName : pwmTable)
     {