diff --git a/instrument/CORELLI_Parameters.xml b/instrument/CORELLI_Parameters.xml
index 70723673bd72e7199cc9afa2353ac865f892669d..b560efec73c1cd93385ca7ed68564c689f3ad500 100644
--- a/instrument/CORELLI_Parameters.xml
+++ b/instrument/CORELLI_Parameters.xml
@@ -30,6 +30,16 @@
      <value val="2." />
     </parameter>
 
+    <!-- Number of rows between detector gaps for profile fitting -->
+    <parameter name="numDetRows" type="int">
+     <value val="255" />
+    </parameter>
+
+    <!-- Number of cols between detector gaps for profile fitting -->
+    <parameter name="numDetCols" type="int">
+     <value val="16" />
+    </parameter>
+
   </component-link>
 
 </parameter-file>
diff --git a/instrument/MANDI_Parameters.xml b/instrument/MANDI_Parameters.xml
index fcae38355cdb9e04e2b3204788c01beb7e40f9f8..8833ec7f5d2683aab7531444d12c1d848f0ea291 100644
--- a/instrument/MANDI_Parameters.xml
+++ b/instrument/MANDI_Parameters.xml
@@ -23,6 +23,17 @@
  <value val="2." />
 </parameter>
 
+<!-- Number of rows between detector gaps for profile fitting -->
+<parameter name="numDetRows" type="int">
+ <value val="255" />
+</parameter>
+
+<!-- Number of cols between detector gaps for profile fitting -->
+<parameter name="numDetCols" type="int">
+ <value val="255" />
+</parameter>
+
+
 
 </component-link>
 
diff --git a/instrument/MANDI_Parameters_2015_08_01.xml b/instrument/MANDI_Parameters_2015_08_01.xml
index 1f51ed8abe27fd1f34b99edf6a7bc68345ac2d34..656e899ba714c327f673a32cec910509ffe66c4e 100644
--- a/instrument/MANDI_Parameters_2015_08_01.xml
+++ b/instrument/MANDI_Parameters_2015_08_01.xml
@@ -23,6 +23,16 @@
  <value val="2." />
 </parameter>
 
+<!-- Number of rows between detector gaps for profile fitting -->
+<parameter name="numDetRows" type="int">
+ <value val="255" />
+</parameter>
+
+<!-- Number of cols between detector gaps for profile fitting -->
+<parameter name="numDetCols" type="int">
+ <value val="255" />
+</parameter>
+
 
 
 </parameter-file>
diff --git a/instrument/MANDI_Parameters_2016_02_01.xml b/instrument/MANDI_Parameters_2016_02_01.xml
index e5f07a3373eca01fbf05518fdc484abee74f05c3..c3471773d9fc8a338907a93c18d8017cce6b848b 100644
--- a/instrument/MANDI_Parameters_2016_02_01.xml
+++ b/instrument/MANDI_Parameters_2016_02_01.xml
@@ -23,4 +23,14 @@
  <value val="2." />
 </parameter>
 
+<!-- Number of rows between detector gaps for profile fitting -->
+<parameter name="numDetRows" type="int">
+ <value val="255" />
+</parameter>
+
+<!-- Number of cols between detector gaps for profile fitting -->
+<parameter name="numDetCols" type="int">
+ <value val="255" />
+</parameter>
+
 </parameter-file>
diff --git a/instrument/TOPAZ_Parameters.xml b/instrument/TOPAZ_Parameters.xml
index 4ef8ded71a59b552fd7fa8d4f81e0017ee032a39..0151036048a5a26c7aa4f368c81d67280df32d0b 100644
--- a/instrument/TOPAZ_Parameters.xml
+++ b/instrument/TOPAZ_Parameters.xml
@@ -99,6 +99,17 @@ detScale={13:1.046504,14:1.259293,16:1.02449,17:1.18898,18:0.88014,19:0.98665,\
  <value val="3." />
 </parameter>
 
+<!-- Number of rows between detector gaps for profile fitting -->
+<parameter name="numDetRows" type="int">
+ <value val="255" />
+</parameter>
+
+<!-- Number of cols between detector gaps for profile fitting -->
+<parameter name="numDetCols" type="int">
+ <value val="255" />
+</parameter>
+
+
 </component-link>
 
 </parameter-file>
diff --git a/scripts/SCD_Reduction/BVGFitTools.py b/scripts/SCD_Reduction/BVGFitTools.py
index 4c1f154fbc250a2cc814507e67223fbbddde83cb..1620d1a476b6922245613b99df1b675773d04a33 100644
--- a/scripts/SCD_Reduction/BVGFitTools.py
+++ b/scripts/SCD_Reduction/BVGFitTools.py
@@ -77,13 +77,11 @@ def get3DPeak(peak, peaks_ws, box, padeCoefficients, qMask, nTheta=150, nPhi=150
 
     # This section defines detector size to determine if a peak is too
     # close to the edge.  Order is [NROWS, NCOLS].
-    if   instrumentName == 'MANDI':
-        nPixels = [255, 255]
-    elif instrumentName == 'TOPAZ':
-        nPixels = [255, 255]
-    elif instrumentName == 'CORELLI':
-        nPixels = [255,16]
-    else:
+    try:
+        numDetRows = peaks_ws.getInstrument().getIntParameter("numDetRows")[0]
+        numDetCols = peaks_ws.getInstrument().getIntParameter("numDetCols")[0]
+        nPixels = [numDetRows, numDetCols]
+    except:
         raise UserWarning('Instrument name {} not found. Assuming a 255*255 detector!'.format(instrumentName))
         nPixels = [255,255]