diff --git a/machines/common.lua b/machines/common.lua
index 1b77888..fa38072 100644
--- a/machines/common.lua
+++ b/machines/common.lua
@@ -640,7 +640,7 @@ simpleElectricItemProcessor.onMetadataInventoryMove=function(pos,fromList,fromIn
 		if meta:get_int("industrialtest.powerAmount")>0 then
 			meta:set_string("formspec",simpleElectricItemProcessor.getFormspec(pos))
 		end
-	elseif fromList=="dst" and dstSlot:get_free_space()==0 then
+	elseif fromList=="dst" and dstSlot:get_free_space()>0 then
 		minetest.get_node_timer(pos):start(industrialtest.updateDelay)
 	end
 end
@@ -656,7 +656,7 @@ simpleElectricItemProcessor.onMetadataInventoryTake=function(pos,listname,index,
 		if meta:get_int("industrialtest.powerAmount")>0 then
 			meta:set_string("formspec",simpleElectricItemProcessor.getFormspec(pos))
 		end
-	elseif listname=="dst" and dstSlot:get_free_space()==0 then
+	elseif listname=="dst" and dstSlot:get_free_space()>0 then
 		minetest.get_node_timer(pos):start(industrialtest.updateDelay)
 	end
 end