diff --git a/src/classes/PRunDataHandler.cpp b/src/classes/PRunDataHandler.cpp
index 5e5cb616..386f3a5a 100644
--- a/src/classes/PRunDataHandler.cpp
+++ b/src/classes/PRunDataHandler.cpp
@@ -2055,11 +2055,15 @@ Bool_t PRunDataHandler::ReadRootFile()
         }
 
         dataSet.Clear();
-        dataSet.SetName(histo->GetTitle());
+        dataSet.SetTitle(histo->GetTitle());
         dataSet.SetHistoNo(redGreenOffsets[i]+j+1);
 
         // get detector info
         path.Form("DetectorInfo/Detector%03d/", redGreenOffsets[i]+j+1);
+        pathName = path + "Name";
+        header->Get(pathName, str, ok);
+        if (ok)
+          dataSet.SetName(str);
         pathName = path + "Time Zero Bin";
         header->Get(pathName, dval, ok);
         if (ok)
@@ -5582,6 +5586,29 @@ Bool_t PRunDataHandler::WritePsiBinFile(TString fln)
   Int_t ival = 0;
   PRawRunDataSet *dataSet;
   UInt_t size = fData[0].GetNoOfHistos();
+  // collect histo names in order to see if they are still unique after cropping to 4 char.
+  PStringVector hName, hNCrop;
+  TString sCrop;
+  for (UInt_t i=0; i<size; i++) {
+    dataSet = fData[0].GetDataSet(i, false); // i.e. the false means, that i is the index and NOT the histo number
+    // detector name
+    str = dataSet->GetName();
+    hName.push_back(str);
+    sCrop = str;
+    sCrop.Remove(4);
+    hNCrop.push_back(sCrop);
+  }
+  // check cropped for uniqueness
+  ival = 1;
+  for (UInt_t i=0; i<size; i++) {
+    for (UInt_t j=i+1; j<size; j++) {
+      if (hNCrop[i] == hNCrop[j]) {
+        std::string nn = std::to_string(ival);
+        hNCrop[j][3] = nn[0];
+      }
+    }
+  }
+  // handle rest of the detectors
   for (UInt_t i=0; i<size; i++) {
     dataSet = fData[0].GetDataSet(i, false); // i.e. the false means, that i is the index and NOT the histo number
     if (dataSet == nullptr) { // something is really wrong
@@ -5591,10 +5618,7 @@ Bool_t PRunDataHandler::WritePsiBinFile(TString fln)
     }
 
     // detector name
-    str = dataSet->GetName();
-    if (!str.CompareTo("n/a"))
-      str.Form("Detector%3d", i+1);
-    psibin.PutNameHisto(str.Data(), i);
+    psibin.PutNameHisto(hNCrop[i].Data(), i);
     // time zero bin
     ival = static_cast<Int_t>(dataSet->GetTimeZeroBin()/fAny2ManyInfo->rebin);
     psibin.PutT0Int(i, ival);