rockman7892
Electrical
Looking for opinions and experience with secondary protection in a customer owned HV industrial substation which supplies power to customer processing facility. Existing substation is being re-built and there is some discussion on weather or not to include secondary 13.2kV breaker on low side of transformer vs a switch for cost saving measures.
Substation is fed at 60kV from utility through customer owned 60kV breaker, stepped down via 6MVA 60kV-13.2kV transformer, and currently has a 13.2kV breaker on secondary before main plant feeder travels overhead several hundred yards to facility main gear.
The substation has a transformer relay providing overcurrent protection on high side, and diff zone between existing high side and low side breakers. With the rebuild of the new sub there is discussion if the existing 13.2kV breaker can be replaced with a switch (non fault interrupting) to save costs. This would simply be an isolation switch that would not have fault break capability.
In my experience I've always seen industrial subs have a secondary main breaker before feeding into plant, or in the instances they didn't had cable diff protection on the secondary cable feeding into plant. Looking for any experience, opinions, and code requirements from others on pros vs cons for keeping breaker vs switch.
Thanks
Substation is fed at 60kV from utility through customer owned 60kV breaker, stepped down via 6MVA 60kV-13.2kV transformer, and currently has a 13.2kV breaker on secondary before main plant feeder travels overhead several hundred yards to facility main gear.
The substation has a transformer relay providing overcurrent protection on high side, and diff zone between existing high side and low side breakers. With the rebuild of the new sub there is discussion if the existing 13.2kV breaker can be replaced with a switch (non fault interrupting) to save costs. This would simply be an isolation switch that would not have fault break capability.
In my experience I've always seen industrial subs have a secondary main breaker before feeding into plant, or in the instances they didn't had cable diff protection on the secondary cable feeding into plant. Looking for any experience, opinions, and code requirements from others on pros vs cons for keeping breaker vs switch.
Thanks