diff --git a/Framework/PythonInterface/test/python/plugins/algorithms/SetDetScaleTest.py b/Framework/PythonInterface/test/python/plugins/algorithms/SetDetScaleTest.py
index 37d1cb2e454b4c0924cff36ea7f69e35582426ea..025e469042c453dbbb7fc83b05caa5de3477c294 100644
--- a/Framework/PythonInterface/test/python/plugins/algorithms/SetDetScaleTest.py
+++ b/Framework/PythonInterface/test/python/plugins/algorithms/SetDetScaleTest.py
@@ -9,7 +9,7 @@ from mantid.api import *
 class SetDetScaleTest(unittest.TestCase):
 
     def testScaleDetectors(self):
-        w = LoadIsawPeaks('TOPAZ_3007.peaks')
+        w = LoadNexusProcessed('TOPAZ_3007.peaks.nxs')
         x = w.getInstrument().getNumberParameter("detScale17")[0]
         y = w.getInstrument().getNumberParameter("detScale49")[0]
         self.assertEqual(x, 1.18898)