Term
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Definition
Provides Power to 4KV motors, 480 and 230 distribution systems via stepdown transformers necessary for:
1. Normal Plant operation
2. Safe Sutdown for the following conditions: Normal,Transient,Accident |
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Term
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Definition
Capable of being safely shutdown from full power in the event of loss OSP.
Total loss of onsite and offsite AC power is NOT a design basis. |
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Term
| Which SPTs feed the 4KV group buses? |
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Definition
1H and 1E fed from 11 SPT,
1F and 1G fed from 12 SPT,
2H and 2E fed from 21 SPT,
2F and 2G fed from 22 SPT |
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Term
| Under normal opertaion, how do the 4KV group buses receive power? |
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Definition
| The group buses are typically fed through thier respective APTs. |
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Term
| What SPTs feed the 4KV vital buses? |
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Definition
| 13 SPT, 14 SPT, 23 SPT and 24 SPT |
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Term
| Typical breaker lineup of 4KV vital buses are: |
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Definition
2 infeed breakers from 1 SPT and
1 infeed breaker from the other SPT
14 SPT feeds 14 BSD and
14 CSD and 13 SPT feeds 13 ASD |
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Term
During a loss of power from 24 SPT,
what is the normal lineup of the CW breakers? |
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Definition
24CW9AD is open
2CW2BD is closed
23CW1AD is closed
The 460/240V CW bus that feeds the travelling screens would be lost in this situation. Thus, the need for the cross tie breaker to close. |
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Term
| Describe a manual transfer from one 4KV infeed breaker to the other 4KV infeed breaker. |
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Definition
Close command given to the open breaker.
Clsed breaker receives open signal and opens. Upon opening, the bus deenergizes past 35%, allowing the desired breaker to close. |
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Term
What are the 2 types of undervoltage relays
and what are their setpoints? |
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Definition
UV = less than 70%
Degraded voltage relay = 95.1 |
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Term
| To swap from one 4KV infeed breaker to another, Bus transfer interlock must meet what % undervoltage before breaker closure? |
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Definition
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