208volt Problem at Marinas

[caltexflanc]

If you have isolation transformers on your boat, you should see if they are tapable. Quite a bit of discussion on this at The Hatteras Owners Forum if you search the archives. The OEM transformers on the Hattes allowed you to put a switchable tap in place and you could boost voltage 10% when switched. A lot of owners did this on a DIY basis, putting the switch on the panel with the voltmeter. Just have to remember to turn it off when you leave for the next dock, and to keep an eye on voltage in case it is a matter of being erratic due to loads or permanently low.

 

[tiltrider1]

I would go the direction of a 208/240 step up transformer. You would need an automatic voltage sensing switch to bypass the transformer when you are on the generator or at a 240v dock. Easy and simple except for the cost of the transformer.

Diver Dave probably has the right idea. I have not really researched the idea so I can’t say weather to go with just a transformer for the ice machine or the whole boat.

 

[diver dave]

You dont want to do the entire boat. Only the “real” 240v loads. If you did the entire boat, the 120v loads get now 132v nominal. Its messy, but you want to divorce only the 240v loads and make it an option to boost only those 15%. And i would want automatic.
As you switch from gen to shore it requires yet another step if its manual.

 

[diver dave]

More bad news. If these 240v appliances also need 120v for controls/lights it gets very messy.

 

[tiltrider1]

More bad news. If these 240v appliances also need 120v for controls/lights it gets very messy.

Why Dave, the appliance is only going to see 240v and will step down to 120v internally if needed, or 12v if that’s needed.

Based on diver dave’s Concerns it appears the simplest solution is to just step up the ice machine. Stepping up the entire 240v side of the boat is going to require some rewiring of the panel. It can be done easily enough but will take a good chunk of time and more wire.

If stepping up the whole boat, each hot leg will be split right after the main breaker. One split to the 120v panel, the second split to the step up transformer. Same for the other hot leg. The 240v breakers will have their feed line removed from each side of the 120v panel and rerouted to the transformer. Some were in their will be a voltage sensing switch that can bypass the step up transformer if the transformer doesn’t have it built in.

 

[diver dave]

Why Dave, the appliance is only going to see 240v and will step down to 120v internally if needed, or 12v if that’s needed.

Based on diver dave’s Concerns it appears the simplest solution is to just step up the ice machine. Stepping up the entire 240v side of the boat is going to require some rewiring of the panel. It can be done easily enough but will take a good chunk of time and more wire.

If stepping up the whole boat, each hot leg will be split right after the main breaker. One split to the 120v panel, the second split to the step up transformer. Same for the other hot leg. The 240v breakers will have their feed line removed from each side of the 120v panel and rerouted to the transformer. Some were in their will be a voltage sensing switch that can bypass the step up transformer if the transformer doesn’t have it built in.

As you say for a straight 240V item. If that item has a neutral run to it, and if it also requires 120V, the story changes significantly. Why, because when you increase the hot leg on each side of 208 to 230, you also increase the leg to neutral voltage from 120 to 132V. If the icemaker, for instance, doesn't use 120V, then no issue. Understand, though, that most household 240V users also need 120V to operate. Water heater being an exception.

 

[tiltrider1]

Yep, your right, I was watching football and I brain farted. So if the ice maker uses 120v internally then best option would be to take a 120v and step up to 240.