Hello Everyone:
I'm working on a project where we require to add a fire pump to an existing facility. This facility has three services (480Y/277V, 240V & 208Y/120V). Two of the 1000KVA substations (208/120V & 240V) are located on the 1st floor. The 480V substation is located on the roof. All substations line-up are located indoor (13.8 MV Gear, Transformer & secondary voltage gear). The 240V substation has all three components (MV gear, Transformer, LV Gear) on the same line up. The 208/120V substation has the transformer section by it self due to space limitation. My first thought was to tap from the 240V/Delta transformer section (since it's used to serve all 3-Phase equipment) but not sure if phase "B" grounded or not or would cause any problems if this transformer is not grounded (it's an old facility-office type building). My second choice will be tapping from the 208V/120V transformer section. My questions to you:
1. Is there any issue by tapping from the secondary of the transformer section and run cables (2-hrs rated) to the fire pump controller? My understanding we can't tap from the same section of the main disconnecting mean.
2. What kind of modification I need to do to land these cables at the tap? do we need to change the lugs so it can accommodate the fire pump cables?. (I'm not doing the actual work but need to write the scope)
P.s. The facility has reliable power.
Your help is really appreciated!
I'm working on a project where we require to add a fire pump to an existing facility. This facility has three services (480Y/277V, 240V & 208Y/120V). Two of the 1000KVA substations (208/120V & 240V) are located on the 1st floor. The 480V substation is located on the roof. All substations line-up are located indoor (13.8 MV Gear, Transformer & secondary voltage gear). The 240V substation has all three components (MV gear, Transformer, LV Gear) on the same line up. The 208/120V substation has the transformer section by it self due to space limitation. My first thought was to tap from the 240V/Delta transformer section (since it's used to serve all 3-Phase equipment) but not sure if phase "B" grounded or not or would cause any problems if this transformer is not grounded (it's an old facility-office type building). My second choice will be tapping from the 208V/120V transformer section. My questions to you:
1. Is there any issue by tapping from the secondary of the transformer section and run cables (2-hrs rated) to the fire pump controller? My understanding we can't tap from the same section of the main disconnecting mean.
2. What kind of modification I need to do to land these cables at the tap? do we need to change the lugs so it can accommodate the fire pump cables?. (I'm not doing the actual work but need to write the scope)
P.s. The facility has reliable power.
Your help is really appreciated!