Broken protectors are the remnants of pre-apocalyptic security systems originally designed to secure bunkers and houses from thieves and raiders. A broken protector is basically a decayed version of a normal protector, with one important difference: it can be mined. The game automatically generates broken protectors when a world is created. Broken protectors have the same protective radius as a regular protector (i.e., about 15 blocks).
How to Obtain
This item cannot be obtained into player inventory. Mining it destroys it.
How to Destroy
You'll need Engineering Skill level 3 to destroy this item. Use a pick, shovel, or spade. Other melee weapons won't work. Mining a broken protector will give you a small amount of XP, but does NOT count as raiding a dungeon.
This type of protector is what protects the much-coveted painting dungeon. It also protects ice sculpture bunkers in arctic worlds. It can often be found in surface houses, protecting a red chest, as well.
As of March 2016, PC players (and other v3 users) are not able to see the protector radius of broken protectors.