jtinge
Senior Member
- Location
- Hampton, VA
- Occupation
- Sr. Elec. Engr
We are replacing the station service transformer in our customer-owned substation with three single-phase, platform-mounted distribution transformers connected delta-wye to provide 208/120V. The secondary will feed a local fused disconnect switch which then feeds a panelboard.
The attatched sketch reflects my understanding of how the grounding and bonding of the transformers and the disconnect switch should be implemented based on 2014 NEC and separately derived system (SDS) grounding requirements.
Since these distribution transformers are typically installed as pole-mounted transformers as a utility owned service, have I correctly applied grounding requirements for them when platform-mounted as an SDS?
Based on 2014 NEC, does a supply-side bonding jumper need to be connected from the disconnect switch to the tanks of the three transformers?
The attatched sketch reflects my understanding of how the grounding and bonding of the transformers and the disconnect switch should be implemented based on 2014 NEC and separately derived system (SDS) grounding requirements.
Since these distribution transformers are typically installed as pole-mounted transformers as a utility owned service, have I correctly applied grounding requirements for them when platform-mounted as an SDS?
Based on 2014 NEC, does a supply-side bonding jumper need to be connected from the disconnect switch to the tanks of the three transformers?