diff --git a/cables.lua b/cables.lua
index 83850bb..a8be0c1 100644
--- a/cables.lua
+++ b/cables.lua
@@ -15,6 +15,20 @@
 -- along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 local S=minetest.get_translator("industrialtest")
+local cable={}
+
+cable.onConstruct=function(pos)
+	local connections=industrialtest.api.getConnections(pos)
+	for _,conn in ipairs(connections) do
+		local meta=minetest.get_meta(conn)
+		local networks=industrialtest.api.isAttachedToNetwork(meta)
+		if networks then
+			for _,network in ipairs(networks) do
+				industrialtest.api.createNetworkMapForNode(network)
+			end
+		end
+	end
+end
 
 local function registerCable(name,displayName,size,flow,registerInsulated)
 	local definition={
@@ -88,7 +102,8 @@ local function registerCable(name,displayName,size,flow,registerInsulated)
 			"group:_industrialtest_hasPowerInput",
 			"group:_industrialtest_hasPowerOutput",
 			"group:_industrialtest_cable"
-		}
+		},
+		on_construct=cable.onConstruct
 	}
 	if industrialtest.mtgAvailable then
 		definition.groups={
diff --git a/machines/common.lua b/machines/common.lua
index 138e5cd..a8f26d5 100644
--- a/machines/common.lua
+++ b/machines/common.lua
@@ -65,25 +65,30 @@ machine.onConstruct=function(pos,config)
 	industrialtest.api.addPowerStorage(meta,config.capacity,config.flow,config.ioConfig)
 	meta:set_string("formspec",machine.getFormspec(pos,config))
 
-	if config.groups and config.groups._industrialtest_hasPowerInput then
-		local connections=industrialtest.api.getConnections(pos)
-		for _,conn in ipairs(connections) do
-			local connectionMeta=minetest.get_meta(conn)
-			if industrialtest.api.isNetworkMaster(connectionMeta) then
-				industrialtest.api.createNetworkMapForNode(conn)
-			else
-				local def=minetest.registered_nodes[minetest.get_node(conn).name]
-				if def.groups._industrialtest_cable then
-					local networks=industrialtest.api.isAttachedToNetwork(connectionMeta)
-					if networks then
-						for _,network in ipairs(networks) do
-							industrialtest.api.createNetworkMapForNode(network)
-							minetest.get_node_timer(network):start(industrialtest.updateDelay)
+	if config.groups then
+		if config.groups._industrialtest_hasPowerInput then
+			local connections=industrialtest.api.getConnections(pos)
+			for _,conn in ipairs(connections) do
+				local connectionMeta=minetest.get_meta(conn)
+				if industrialtest.api.isNetworkMaster(connectionMeta) then
+					industrialtest.api.createNetworkMapForNode(conn)
+				else
+					local def=minetest.registered_nodes[minetest.get_node(conn).name]
+					if def.groups._industrialtest_cable then
+						local networks=industrialtest.api.isAttachedToNetwork(connectionMeta)
+						if networks then
+							for _,network in ipairs(networks) do
+								industrialtest.api.createNetworkMapForNode(network)
+								minetest.get_node_timer(network):start(industrialtest.updateDelay)
+							end
 						end
 					end
 				end
 			end
 		end
+		if config.groups._industrialtest_hasPowerOutput then
+			meta:set_string("industrialtest.network",minetest.serialize(industrialtest.api.createNetworkMap(pos)))
+		end
 	end
 
 	if config.onConstruct then
diff --git a/machines/generator.lua b/machines/generator.lua
index 4d9eaaa..5cdc291 100644
--- a/machines/generator.lua
+++ b/machines/generator.lua
@@ -55,7 +55,6 @@ generator.onConstruct=function(pos,meta,inv)
 	inv:set_size("fuel",1)
 	meta:set_int("fuelTime",0)
 	meta:set_int("maxFuelTime",1)
-	meta:set_string("industrialtest.network",minetest.serialize(industrialtest.api.createNetworkMap(pos)))
 end
 
 generator.onTimer=function(pos,elapsed,meta,inv)