Adding shore power.

[BubbleheadMd]

Originally Posted by mitiempo

I try not to combine circuits whenever possible. On my own boat I have the Blue Seas 8027 AC panel - double breaker main with 6 circuits. Every outlet is on its own circuit (4) and the charger and 120 volt heater (built-in) are each on their own circuit as well. I have to be concerned about the total usage relative to dock amperage but don't have to worry about individual circuits.

Exactly. If I had a 30 amp breaker, but tied all of the outlets to a 15amp branch breaker, then I'd never be able to use all 30 amps available. Sure, you could run wire capable of 30 amps to the outlets, but the outlets themselves are still only rated for 15 or maybe 20 amps max (depending on which you buy).

Here's my hypothetical energy budget:

Small dehumidifier: 4.35 amps
1000w microwave: 8.30 amps
Dorm fridge: 3amps startup/2amps running
1500w electric heater: 12.5 amps
_______________________________

If all outlets are tied to a single, 15a branch breaker, then the heater alone exceeds 80% of the max load of the 15amp branch breaker. No matter where the appliances are plugged in, if I turn them on, I'll pop the breaker.

If I install two 15a branch breakers, and plug the heater into one outlet, and the other appliances into the other outlet, then I'm at no more than 80% per breaker, per outlet and I get to use all 30 amps available.

I took my measurements last night, and for me, the 8099 is really the only way to go. I still had to pick a slightly different spot to install it, but it should all work out. Going to be a lot of cutting...

[tap]

Originally Posted by BubbleheadMd

It would be very easy to upgrade to 50 amp service in the future if I suddenly became an energy hog by replacing the 8077 with an 8079.

To upgrade to 50A you would also need to get a 50A shore power inlet and use 6 ga wire from the inlet to the first breaker. And you'd need a 50A shore power cable too of course.

But that may be irrelevant. Does your marina even have 50A service in the 30' slips? In my experience you need to be a 40'+ slip before 50A service is provided.

[BubbleheadMd]

Originally Posted by tap

To upgrade to 50A you would also need to get a 50A shore power inlet and use 6 ga wire from the inlet to the first breaker. And you'd need a 50A shore power cable too of course.

But that may be irrelevant. Does your marina even have 50A service in the 30' slips? In my experience you need to be a 40'+ slip before 50A service is provided.

Yep, I'm aware of this. The distance from the inlet to the first breaker will be pretty short, and everything is pretty accessible. I'm not doing it because as you say, I'm not sure how common 50 amp service is, and because it's a higher cost to set up.

My home dock is 30 amps, but I'm not sure what I'll find out there at other marinas.

[mitiempo]

On many boats with 50 amp service they also have a 30 amp inlet, often going to separate parts of a large panel and with switching to allow one cord to power part or all of the panel. You will find 30 amp virtually everywhere, and docks sized for larger boats often have 50 amp service as well. Slips for boats 30' or so rarely have any service but 30 amp.

You have no need for 50 amp service until you install the washer/dryer anyway.

[BubbleheadMd]

I think you're right, and that I'm going overkill on this. I'll just stick to my 30amp plan.

[sailhound104]

I have an Ericson 32 that has shore power connected, but only to a single outlet. I would like to be able use the onboard electronics and lights without draining my aux battery while at shore. Is it possible to install a switch to enable the shore power to run my onboard equipment wired for DC, or do I need to install a battery charger to make this happen? And if that is the case, do I need a swith to toggle between the alternator and the 110 battery charger?

Thanks,
ALex

[mitiempo]

What kind of circuit breaker do you have?

Your shore power should go to a double breaker and then to the breakers for the other circuits after that. Anything less is not as safe as it should be.

To run 12 volt accessories off of share power you need either a power supply or a charger. A switch will not work. The charger makes the most sense and it should be a marine charger on its own breaker.

You do not need a switch between the alternator and charger.

[sailhound104]

It looks like a single 15. I'm guessing I'll have to bump that up to a 30?

Thanks,
Alex

[mitiempo]

Yes, like this:

[sailhound104]

Excuse my ignorance, but is that 2x30 amps or 2x15?

Thanks,
Alex