Index: trunk/FACT++/src/biasctrl.cc
===================================================================
--- trunk/FACT++/src/biasctrl.cc	(revision 12210)
+++ trunk/FACT++/src/biasctrl.cc	(revision 12211)
@@ -891,5 +891,5 @@
             if (offset[ch]<-90 || offset[ch]>90)
             {
-                Error("AddVolt - Offset out of range [-90V,90V].");
+                Error("AddVolt - Offset " << offset[ch] << " for channel " << ch << " out of range [-90V,90V].");
                 return false;
             }
@@ -966,5 +966,5 @@
         if (offset<-90 || offset>90)
         {
-            Error("SetGapdVoltage - Offset out of range [-90V,90V].");
+            Error("SetGapdVoltage - Offset " << offset << " out of range [-90V,90V].");
             return false;
         }