Being I normally do not design medium voltage systems, I could use some input as to whether the following design meets code for protection and grounding.
A pumping station in a rural area is replacing a 150hp, 480V motor with a 400hp, 2300V motor. The utility will provide (3) 7200V ? 2400V pole mounted transformers and the 2400V, 3 phase 3W service to the customer NEMA 4X, 5KV pad mounted switchgear. The utility system is 12,470Y/7200V.
The (3) section switchgear has a main disconnect (requested by the utility) at 600A, 20A fused disconnect to feed a 2400V-480Y/277V pad mount transformer (replacing the existing 480V 3 phase, 3W service to the MCC and control panels in the control room), and a 150A fused disconnect to feed the motor starter for the new 400hp pump motor.
The service switchgear metal enclosure will be grounded to the concrete pad rebar as well as (2) ground wells. The 75KVA transformer is 10? away from the switchgear and will be grounded and bonded at the secondary to an ufer ground and (2) ground wells. The neutral will be run to the control room 100A main disconnect and bonded to the ground terminal.
The motor starter will have a new Multilin 269 Plus relay with 50/5A ground fault CT to protect against ground faults.
The question is does this meet code and / or see any obvious problems? I appreciate any responses.
A pumping station in a rural area is replacing a 150hp, 480V motor with a 400hp, 2300V motor. The utility will provide (3) 7200V ? 2400V pole mounted transformers and the 2400V, 3 phase 3W service to the customer NEMA 4X, 5KV pad mounted switchgear. The utility system is 12,470Y/7200V.
The (3) section switchgear has a main disconnect (requested by the utility) at 600A, 20A fused disconnect to feed a 2400V-480Y/277V pad mount transformer (replacing the existing 480V 3 phase, 3W service to the MCC and control panels in the control room), and a 150A fused disconnect to feed the motor starter for the new 400hp pump motor.
The service switchgear metal enclosure will be grounded to the concrete pad rebar as well as (2) ground wells. The 75KVA transformer is 10? away from the switchgear and will be grounded and bonded at the secondary to an ufer ground and (2) ground wells. The neutral will be run to the control room 100A main disconnect and bonded to the ground terminal.
The motor starter will have a new Multilin 269 Plus relay with 50/5A ground fault CT to protect against ground faults.
The question is does this meet code and / or see any obvious problems? I appreciate any responses.