Network Equipment. Presented By: Jock Moffat Network Protector Consulting Services, LLC. Network Equipment. Transformers Protectors Relays. Transformers Protectors Relays. Network Equipment. Network Transformers . General Information
Presented By: Jock Moffat
Consulting Services, LLC
Grid Network applications
Spot Network applications
Low Voltage 216Y/125V - 300, 500, 750 and 1000 kVA
Low Voltage 480Y/277V - 500, 750, 1000, 1500,
2000 and 2500 kVA
History – In 1932 polychlorinated biphenyl (PCB) was the insulating fluid of choice.
Mineral Oil is the most common insulating fluid in use.
Buildings with inside vaults needed high fire point (non flammable) fluids. For a premium price the available choices are:
Taller buildings required transformers to be installed inside the building many floors above ground level.
Will the transformer be subjected to water?
Standardized throat design allows equipment to be interchangeable with different manufacturers.
The main tank and high voltage switch will be provided with sampling valves to assist in oil testing.
Usually the transformer nameplate will be attached to the outside of the high voltage chamber to allow for easy viewing.Transformer Tank
3 Pole, 3 Position Switch
Types of Switches available
Use 2 electrical interlocks.
Top Oil temperature indicator
Oil Level gauge
Most utilities establish annual vault inspection schedules and perform visual inspections and minor maintenance during this visit.
Perform dielectric and DGA testing
What is a network protector ?
A network protector is an automatic air circuit breaker installed between the secondary side of the network transformer and the secondary network.
It must open when the feeder is opened or faulted.
The protector should open to prevent reverse current flow from the secondary network to the substation. Back-feed current is an abnormal condition and a safety hazard.
The protector should close when conditions allow power to flow from the transformer to the secondary network.
Interrupting rating must exceed the transformer maximum thru-fault value.
Note: (consult nameplate for actual ratings)