Electrical upgrade 2000 Hunter 320

Jan 24, 2018
5
Hunter 320 North Vancouver
Hi All. We have to make some electrical upgrades in order to accommodate our icebox conversion and master flush 7100 toilet. We have two spare breakers. One is a 10amp, the other 15 amp. To run the new equipment we need is a 20amp and 25amp. The main breaker to the DC panel is 50 amps. Will this need to be upgraded? Thanks for any thoughts you may have on this. Cheers
 
Jan 8, 2015
360
MacGregor 26S, Goman Express 30 Kerr Reservoir
[QUOTE=" The main breaker to the DC panel is 50 amps. Will this need to be upgraded? [/QUOTE]

No Dress,
It depends on what extent you intend to upgrade. If you only intend on replacing the 50 amp breaker with a larger one, don't do it. If you intend on replacing the service panel with a higher capacity model, then the next component you will have to replace is the shore power cord to handle the larger amperage. Then you will have to find a marina that has greater than 50 amp service. (not likely)
A simpler solution, after you replace the spare breakers with larger ones is to limit your simultaneous usage of high draw electrical loads. e.g. don't operate the master flush 7100 toilet while using the microwave when the A/C is running.
 
May 17, 2004
5,071
Beneteau Oceanis 37 Havre de Grace
No Dress,
It depends on what extent you intend to upgrade. If you only intend on replacing the 50 amp breaker with a larger one, don't do it. If you intend on replacing the service panel with a higher capacity model, then the next component you will have to replace is the shore power cord to handle the larger amperage. Then you will have to find a marina that has greater than 50 amp service. (not likely)
A simpler solution, after you replace the spare breakers with larger ones is to limit your simultaneous usage of high draw electrical loads. e.g. don't operate the master flush 7100 toilet while using the microwave when the A/C is running.
He said it's a 50 amp breaker on his DC panel, so I presume we're not talking about the AC side.

As you the other loads you may expect when you're running the 20 and 25 amp loads. If nothing that runs concurrently approaches 50 amps then you probably don't need to change that breaker. You will need to install new larger breakers for the new components, and be sure to use large enough wire to carry that current from the breaker to the appliances. If you do need to upgrade the 50A breaker then at a minimum you'll need to increase the wire gauge to the panel.
 
Jun 6, 2006
6,990
currently boatless wishing Harrington Harbor North, MD
No need to upgrade the AC or shore power cables/find a new 50 amp slip. the AC will only see the current AC loads like battery charger, heater etc. Adding to the DC panel will probably not require an upgrade master CB either as long as you understand you may be entering into the no concurrent use regime. By that I mean you can run all the stuff you want as long as the sum of the amps is not above the 50 amp limit. the main CB is usually a "slow blow" so if you run it at 52 amps for a second or two it will not trip. if you run the main CB at 50 amps for something like 15 minutes it will trip (that is normal BTW). You can run it at 48 amps indefinitely. since your new circuits are a mix of continuous and short term use and they both together don't add up to 50 amps you should be fine. Do need to monitor your other circuits like house lights, nav lights, etc so that you don't exceed the master CB capacity when you run them at the same time. A DC panel ammeter is helpful for this.
 
Jan 11, 2014
11,401
Sabre 362 113 Fair Haven, NY
Another part to consider is the wire size supplying the main panel. That wire size should be large enough to handle any loads and be protected by an appropriate sized breaker. If you breakers start tripping with the new icebox and toilet, then the panel breaker will need to be up graded, the wire supplying it will need to be up graded, and perhaps the first circuit breaker/fuse on the main circuit upgraded.

With your new additions, most of the time it shouldn't be an issue, however, if the icebox is running, the lights are on, the stereo on, and someone flushes the head there could be enough current draw to trip the main breaker. Reducing the other loads or not flushing while cooling will help avoid this problem.
 
Jan 22, 2008
8,050
Beneteau 323 Annapolis MD
those PRESENT SMALLER BREAKERS PROBABLY HAVE LARGER WIRE ON THEM. Check that wire size, and maybe just change the breakers. You say you have a 50-amp fuse supplying the DC panel, but what size wire is entering/exiting that breaker?
 
Oct 24, 2010
2,405
Hunter 30 Everett, WA
Just because your new appliances call for 20 and 25 amp breakers doesn't mean they will actually have that much current draw. No doubt they call for large enough breakers that they never trip. Expect actual loads to be a bit less.

Ken