SolarSuperstar
New User
- Location
- Denver, CO
- Occupation
- Engineer
I am trying to figure out whether I need overcurrent protection for several ATS that I have on a utility scale battery project where I have a sizeable emergency aux load to feed battery HVAC.
Situation: I have a local 34.5kV circuit connected to an on-site/project substation feeding several 34.5kV:480V transformers. These transformers have integrated OCPD on the primary that either we or the transformer mfr will spec. The secondary of each transformer, currently without an OCP, will pass through an ATS and hit a 2500A switchboard. The emergency side of the ATS connects to a switchboard with breakers for each ATS. Our current design is to have a breaker in the switchboard downstream of the ATS, but that leaves the ATS unprotected. I'm struggling to find anything in the code (450, 700, 705 etc.) that can help me understand where this OCPD is needed - at the ATS or at the switchgear. The switchgear will be far simpler to implement OCPD within. Any help our guidance would be much appreciated!
Situation: I have a local 34.5kV circuit connected to an on-site/project substation feeding several 34.5kV:480V transformers. These transformers have integrated OCPD on the primary that either we or the transformer mfr will spec. The secondary of each transformer, currently without an OCP, will pass through an ATS and hit a 2500A switchboard. The emergency side of the ATS connects to a switchboard with breakers for each ATS. Our current design is to have a breaker in the switchboard downstream of the ATS, but that leaves the ATS unprotected. I'm struggling to find anything in the code (450, 700, 705 etc.) that can help me understand where this OCPD is needed - at the ATS or at the switchgear. The switchgear will be far simpler to implement OCPD within. Any help our guidance would be much appreciated!
