The NEC discusses oil filled transformers installed indoors must be enclosed in a vault. Does this vault have to basically be a room with a door that is fire rated? Is there anyway to just have a berm for containment and skip the vault room?
I have a situation where we have an existing building that will have a dry type transformer (12kv-4160V) that then feeds a test set that has a HV oil transformer. The way I interpreted the code is that you must enclose this HV transformer in a vault. But right adjacent to this transformer is some switchgear that is also part of the test set. So is a berm required inside the vault that encloses the transformer only, then a vault around all swtichgear components as well? I would think not because the walls of the vault provide spill containment. But at the same time if oil were to spill it wouldn't have any separation from the test set switchgear components.
I have a situation where we have an existing building that will have a dry type transformer (12kv-4160V) that then feeds a test set that has a HV oil transformer. The way I interpreted the code is that you must enclose this HV transformer in a vault. But right adjacent to this transformer is some switchgear that is also part of the test set. So is a berm required inside the vault that encloses the transformer only, then a vault around all swtichgear components as well? I would think not because the walls of the vault provide spill containment. But at the same time if oil were to spill it wouldn't have any separation from the test set switchgear components.
