Marina

[Flash Gordon]

The new marina dock has the sub panel main breaker 600a gfci 30MA breaker trip at the sub panel on the dock when one of the 30a 120v 30MA pedestals trips at the pedestal thus no selective coordination and the whole dock gos black.

The service on the beach is GFPE protected 100 MA and holds.

All the branch circuits in the sub panel on the dock are standard breakers now.

So when the pedestal 30a 30MA gfci ocp trips the branch circuit ocp in the sub panel holds and the main breaker in the sub panel on the dock trips taking out all the other boats .

I’m confused. Not my installation I have no dog in the fight. Why would the installer not just put a standard main breaker in the sub panel and then remove the standard 30a breakers in the sub panel and replace them with 30a 30MA gfci breakers ?

Is the installer trying to save money buy not buying a sub panel full of 30a 30MA gfci breakers?
California installation

 

[synchro]

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So when the pedestal 30a 30MA gfci ocp trips the branch circuit ocp in the sub panel holds and the main breaker in the sub panel on the dock trips taking out all the other boats .
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Is this 30A 30mA ground fault protection (GFPE) inside the pedestal provided by a breaker? If so, then the circuit in the subpanel supplying this breaker qualifies as a feeder. 555.35(A) specifies a 100mA level GFPE be provided for feeders. It appears to me that you could have the main breaker in the subpanel be a 100mA GFPE instead of 30mA.

 

[Flash Gordon]

Yes at the pedestal 30mA 30 A. Up stream in the sub panel a standard breaker. Up from that the Main in the sub panel 30Ma GFCI. The beach breaker is GFPE.

It confuses me why there’s no selective coordination.

The pedestal when tripping takes the feeder panel main with it.