diff --git a/.gitignore b/.gitignore
index 5590841..f3b8f7c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -42,4 +42,6 @@ luac.out
 .buildpath
 .project
 org.eclipse.*
-*.lua.new
\ No newline at end of file
+*.lua.new
+
+test_*.lua
\ No newline at end of file
diff --git a/safer_lua/.gitignore b/safer_lua/.gitignore
deleted file mode 100644
index b28395b..0000000
--- a/safer_lua/.gitignore
+++ /dev/null
@@ -1,6 +0,0 @@
-.buildpath
-.project
-org.eclipse.*
-
-
-test_*.lua
\ No newline at end of file
diff --git a/sl_controller/battery.lua b/sl_controller/battery.lua
index 0ab5684..9b93ceb 100644
--- a/sl_controller/battery.lua
+++ b/sl_controller/battery.lua
@@ -51,6 +51,7 @@ minetest.register_node("sl_controller:battery", {
 	after_place_node = function(pos, placer)
 		local meta = minetest.get_meta(pos)
 		meta:set_int("content", sl_controller.battery_capacity)
+		on_timer(pos, 1)
 		minetest.get_node_timer(pos):start(30)
 	end,
 	
@@ -60,6 +61,7 @@ minetest.register_node("sl_controller:battery", {
 	sunlight_propagates = true,
 	paramtype2 = "facedir",
 	groups = {choppy=1, cracky=1, crumbly=1},
+	drop = "",
 	is_ground_content = false,
 	sounds = default.node_sound_stone_defaults(),
 })
diff --git a/sl_controller/controller.lua b/sl_controller/controller.lua
index 78674da..73b2bac 100644
--- a/sl_controller/controller.lua
+++ b/sl_controller/controller.lua
@@ -20,6 +20,9 @@ SaferLua is a subset of Lua with the following restrictions:
  - Limited set of available functions 
  - Store() as alternative to Lua tables
 
+The controller needs a battery nearby.
+Don't remove the battery, it will be destroyed!
+
 See: goo.gl/WRWZgt
 ]]
 
@@ -261,7 +264,7 @@ end
 local function on_timer(pos, elapsed)
 	local t = minetest.get_us_time()
 	local meta = minetest.get_meta(pos)
-	if meta:get_int("state") ~= "running" then
+	if meta:get_int("state") ~= tubelib.RUNNING then
 		return false
 	end
 	local number = meta:get_string("number")