555.3

[charlie b]

Existing marina with very old panels is contemplating upgrades. AHJ is likely to invoke ground fault protection (30ma) requirement (new in 2011 NEC, reduced from 100 ma to 30 ma in 2017). I need to tell the marina owners what to expect. How do we add such protection?

1. How is this different (meaning equipment, not just setpoint) from the GFCI breakers we might install in a residence?
2. Are breakers that have this feature significantly larger (wider) than the existing breakers, so that we may have to replace panels, not just breakers?
3. 555.3 applies to feeders also. The only feeders in the marina are protected by fused disconnects. I believe these would have to be replaced, either by enclosed breakers with ground fault protection or with fused disconnects that include a relay that can kick open the disconnect on a ground fault condition. Is there another way?

 

[Jim1959]

Equipment rated GFCIs (EPDs) are rated at 30 ma, personnel protection GFCIs are rated at 5 ma. In my experience, EPD breakers will fit in a standard breaker space, however with older panels, it would be work checking if they are indeed available and will fit. Another issue might be multi wire branch circuits that may be sharing neutrals. Each circuit will need it's dedicated neutral for single pole EPD breakers to work.

 

[buzzbar]

Existing marina with very old panels is contemplating upgrades. AHJ is likely to invoke ground fault protection (30ma) requirement (new in 2011 NEC, reduced from 100 ma to 30 ma in 2017). I need to tell the marina owners what to expect. How do we add such protection?

1. How is this different (meaning equipment, not just setpoint) from the GFCI breakers we might install in a residence?
2. Are breakers that have this feature significantly larger (wider) than the existing breakers, so that we may have to replace panels, not just breakers?
3. 555.3 applies to feeders also. The only feeders in the marina are protected by fused disconnects. I believe these would have to be replaced, either by enclosed breakers with ground fault protection or with fused disconnects that include a relay that can kick open the disconnect on a ground fault condition. Is there another way?

Charles,
If this is in Washington State, the 30 mA threshold has been delayed (via a WAC Rule) until 7/1/2018. I'm actually on a "committee" that is working on convincing the state to keep it at 100 mA. If possible, it would help your client to get the permit prior to 7-1-2018, because as long as the permit is acquired PRIOR to 7-1-2018, it falls under the existing code.

To answer your questions, it depends on what is being changed. Are they going to change JUST the branch sub feeders on the docks? Or are the main feeders going to the docks also being changed? I am also working on a marina now that is changing JUST the sub feeders on the docks, but the main feeders are being left alone. For now, we are going to provide GFI protection on the docks only, but we'll see what the AHJ has to say.

If they DO need to provide GFI protection for the main feeders, you'll need to change the fused disconnects to circuit breaker enclosures with shunt trips, which are tied to a Bender type GFI system. This is usually the most expensive part. If the branch sub-feeders are in a "normal" panel, the GFI type breakers are the same physical size of the normal breakers. At least they are for Eaton type panels (CH).

Good luck.

-Andy

 

[augie47]

agree,,,

and I might add I know of no solution others than those you mentioned for the fusible disconnects.

 

[charlie b]

If this is in Washington State, the 30 mA threshold has been delayed (via a WAC Rule) until 7/1/2018.

That's just for feeders. Branch circuit protection is required to be 30 ma.

The project is in Washington. Some of the equipment is likely over 40 years old. I have photos that show some GE breakers and some Square D breakers, and some enclosures with no labels at all. They want to upgrade from a single 20 amp pedestal to a pair of 30 amp pedestals for many of the 200+ slips. I think this will certainly require them to add the ground fault protection.

 

[buzzbar]

That's just for feeders. Branch circuit protection is required to be 30 ma.

The project is in Washington. Some of the equipment is likely over 40 years old. I have photos that show some GE breakers and some Square D breakers, and some enclosures with no labels at all. They want to upgrade from a single 20 amp pedestal to a pair of 30 amp pedestals for many of the 200+ slips. I think this will certainly require them to add the ground fault protection.

That's true. There's just a lot of gray areas in retrofit work. But if they are changing the circuits from 20A to 30A, they WILL need to install GFI breakers at the pedestal.

Are they planning on retrofitting existing pedestals with new breakers? What brand are the pedestals? I specialize in marina work, so I can tell you what breakers fit what.

 

[charlie b]

What brand are the pedestals? I specialize in marina work, so I can tell you what breakers fit what.

They are not all the same. But thanks for the offer.

We are in an early stage of evaluations. I am only doing a voltage drop calculation and a service load calculation, both for the present configuration and for the desired future configuration. After that, they will have to decide what they can afford to do. I suspect, very strongly, that a load calculation of the present configuration will show that they are already well beyond the capacity of their service and the feeders.

 

[buzzbar]

They are not all the same. But thanks for the offer.

We are in an early stage of evaluations. I am only doing a voltage drop calculation and a service load calculation, both for the present configuration and for the desired future configuration. After that, they will have to decide what they can afford to do. I suspect, very strongly, that a load calculation of the present configuration will show that they are already well beyond the capacity of their service and the feeders.

Understood. I imagine that if they are all 20A now, that going to 30A will most likely exceed the capacity, but not as much as if they went to 50A receptacles!

 

[jmcdevittcaptain]

555.3

• consider putting to 30mA protection in the power pedestal. Be prepared for tripping when the slip holders power up. You will find that many boats will trip a 30mA device. Of course the boat owners will blame the power pedestal.
  
  NEC really does not specify where the ground fault protection should be installed - just says it need to be 30mA.
  
  Also new in 2017, signage must be displayed in marinas warning of potential hazardous current in the water...
  
  
  John McDevitt
  
  NFPA 302 Watercraft - Chairman