diff --git a/site_ansto/instrument/sans/config/optics/guide_configuration.tcl b/site_ansto/instrument/sans/config/optics/guide_configuration.tcl
index 8ba446a2..75a3c779 100644
--- a/site_ansto/instrument/sans/config/optics/guide_configuration.tcl
+++ b/site_ansto/instrument/sans/config/optics/guide_configuration.tcl
@@ -73,7 +73,7 @@ proc ::optics::set_guide {row} {
     lappend to_config $guide
     lappend to_config [set ${guide}_map($el)] 
   }
-  drive $to_config
+  eval "drive $to_config"
 }
 namespace import ::optics::set_guide