Wanting to plug 15 amp power into boat-problems?

Spyderweb · May 2020

Will be heading up to boat within a few weeks (100 mile trip) to start annual buffing, paint touchup etc. Always wished I could top off the batteries while doing these jobs to better get ready for launch day. Found this 30 amp to 15 amp pigtail to allow me to plug into regular outlet on shore so I could run charger while doing other work.
https://www.ebay.com/itm/352720114461

Then I got to thinking, am I at risk of blowing the (likely) 15 amp breaker to the circuit that I will also likely be plugging my Makita buffer into?
Watts=Amps X Volts or 1800 = 15 X 120. I assume this means I have about 1800 watts available to put on circuit. The PD2130 Charger claims 550 watts, and the buffer at 10 amps would be 1200 watts (1200=10X120). So that's a total of 1750 watts. Though the buffer would be used at less than full speed, hence under 10 amp draw, the startup amp draw is likely significantly higher. So I'm guessing there will be short blasts of over 1800 watts.
Will that trip the breaker?
Would a solution be to unhook some batteries and only charge 1 bank at a time?
Is the real solution to only charge batteries or buff, but not both at same time?

LaRea · May 2020

I don't remember ever popping a breaker when running a buffer and the charger on a 15-amp circuit.

LaRea · May 2020

That's a good price for the adapter.

Aqua_Aura · May 2020

I wouldn't leave it plugged in unattended, not sure how much I would trust cheap plugs who knows how good the internals are.

Spyderweb · May 2020

This would just be used during the day when up there to buff the boat. I too would not trust the cheap plug unattended.

Willhound · May 2020

I do it all the time when prepping boat in spring and when out on the hook with my portable Inverter Generator. Have a decent Marinco adapter though. No problems running it into the system on the boat. I always carry it with me because I've also been in some small marinas that didn't have a 30 amp slip available but had 15.

aero3113 · May 2020

I’ve been using my buffer, charger and dehumidifier all at the same time with an adapter, no issues. I also used a heat gun with the charger and dehumidifier going again no issues.

TonyG13 · May 2020

@Spyderweb - I bought a Y-splitter from this guy on eBay a couple of years ago and when I had a problem with it, I sent him pics of the problem and he sent a replacement no questions asked. Probably why he has a 100% rating. Might want to check him out to see if he has what you need in case you're worried about the seller you found...

https://www.ebay.com/str/ampupmarineandrvcords

Spyderweb · May 2020

@TonyG13, thanks, but I've already bought the adapter. With the limited use it's going to get I think it should be ok, but I'll certainly be keeping track of it while using it.

Sounds like I don't have a full grasp of the relationship between volts, amps, watts and breakers (no surprise to me there). But based on your experiences, sounds like I should be ok with what I'm trying to do. At least I feel better about it now.

mattie · May 2020

Shouldn't be a problem. I have a Marinco adapter to do the same. Used it at marina's with only 15A service on some docks.

Post pics of the buff job when done. Boat porn is always good.

LaRea · May 2020

No, your numbers are right. If everything was drawing full power, you might pop a breaker. But the buffer won't draw full rated power unless you are really, really punishing it.

Just make sure you turn off the other AC loads, like fridges.