no transformers????

[ESCAPE PLAN]

Why would someone remove the transformers from the ER? i know this vessel was wired for euro
also, but what would be the benefit/reason behind this?

 

[Dominion]

I am equally perplexed with this, as I would like to remove. Modern marinas are better wired, but if the unit offers galvanic isolation, as well as constant clean electricity and 240 volts power usage then I would understand leaving. Galvanic isolation is my interest, as Marinas do offer community electrical concerns for free!

 

[Dominion]

Follow-up! Appears this question and or mine was answered in " Wiring Isolation Transformer " thread by rourkeh in 1-17-21, please review

 

[Pascal]

What year is your boat? Are you sure it had transformers? Earlier boats didn’t.

A big benefit of iso transformers is that you don’t need to bring the Neutral on board. In fact many power cords for IT equipped boats don’t even have a neutral wire. Where it pays off is that without neutral you will never trip the new GFCIs that are being installed at so many marinas. Especially with boats using older appliances.

 

[SKYCHENEY]

Since the OP has a boat that was configured for Europe and then brought back to the States, who knows what was done. It may have had 50hz transformers that were removed when it came back here.

 

[Pascal]

Since the OP has a boat that was configured for Europe and then brought back to the States, who knows what was done. It may have had 50hz transformers that were removed when it came back here.

True…. But I don’t think transformers care about frequency, do they?

 

[jmooney]

I could answer this myself if I dug into my wiring diagrams , but I am wondering if the grounds in our electrical panels are tied to the bonding system? Is the neutral tied to the bonding system ? This is on a transformer equipped boat . I remember talking to someone that the neutral on this boat is tied to the bonding system. This is after it was configured for European power , which I think is two wire 240 V .

 

[zigzag930]

My transformers have a 50hz and 60hz setting, done by changing some jumper wires, so at least in my case it would see that transformers are sensitive to frequency.

Boat is 58LRC

 

[Captain Ralph]

I could answer this myself if I dug into my wiring diagrams , but I am wondering if the grounds in our electrical panels are tied to the bonding system? Is the neutral tied to the bonding system ? This is on a transformer equipped boat . I remember talking to someone that the neutral on this boat is tied to the bonding system. This is after it was configured for European power , which I think is two wire 240 V .

I have found boats with transformers wired different ways when it comes to that green wire.
Check the print set for your boat to ensure how your boat is wired and hope nobody has modified it. A DVM could be of use in triple checking this also.

 

[JD5652]

My transformers have a 50hz and 60hz setting, done by changing some jumper wires, so at least in my case it would see that transformers are sensitive to frequency.

Boat is 58LRC

Same here and my transformers are also "Step-Up" or "Step-Down" with the flip of a switch.

Many times on docks the power is not the full 220 VAC. If it is not, then I can step up the voltage so all systems and devices are happy. I can also step it down if needed, but never had to use that function.

 

[madhatter1]

Same here and my transformers are also "Step-Up" or "Step-Down" with the flip of a switch.

Many times on docks the power is not the full 220 VAC. If it is not, then I can step up the voltage so all systems and devices are happy. I can also step it down if needed, but never had to use that function.

I like the idea of a step up switch ( obviously multiple poles to transfer) for docks that only provide 208. But seriously everything on my boat including AC units survive well and perform properly on 208. 1982 vintage.

Funny thing. At a race car event in St Pete many boats had issues with the power. Dock “electrician” claimed there was proper power supplied reading 120v to neutral on both legs yet there was only 208 between phases.

 

[Captain Ralph]

“electrician” claimed there was proper power supplied reading 120v to neutral on both legs yet there was only 208 between phases.

That is correct. Output from a later 3 phase service.

I can try to explain it or you can just trust that was correct and more of it to come as docks and marinas update to these services.

 

[madhatter1]

Single phase or 3 phase the voltage between "hots" is different than adding the voltage of 2 hots together. Mystery transformer stuff to me but although I do not know how I do know it to be true. Ever hear of a high leg? 3 phases, 208 phase to phase (A-B, B-C, A-C) yet 2 phases are 120 to neutral but the third is 208 to neutral. A business friend tried to explain to me but my eyes crossed and I passed out. Maybe Sky can explain in simple terms.

 

[SKYCHENEY]

The high leg is from a Delta 3-phase. You won't see that at a marina.

 

[madhatter1]

The high leg is from a Delta 3-phase. You won't see that at a marina.

Yessir, I know. Was just pointing out that 2 120 leg’s won’t always mean mean 240v. StPete boats show and the Grand Prix docks when in the water are supplied with 208. “Electrician” says all is good because he reads 120 to neutral on each leg. And as I type this wondering if my transformer is the reason I don’t have any issues. If I get 2 120 to neutral legs into the transformer it would make 240 to my panel as a separately derived power source, correct? So I read 208 on the incoming meter yet the boat actually has 240?

Next time I’m on a 208 (heading to Clearwater first trip and they are 208) I’m opening up the panel to meter. If true this is a big reason added to have an isolation txfmr.

 

[Boatsb]

Yessir, I know. Was just pointing out that 2 120 leg’s won’t always mean mean 240v. StPete boats show and the Grand Prix docks when in the water are supplied with 208. “Electrician” says all is good because he reads 120 to neutral on each leg. And as I type this wondering if my transformer is the reason I don’t have any issues. If I get 2 120 to neutral legs into the transformer it would make 240 to my panel as a separately derived power source, correct? So I read 208 on the incoming meter yet the boat actually has 240?樂樂樂

Next time I’m on a 208 (heading to Clearwater first trip and they are 208) I’m opening up the panel to meter. If true this is a big reason added to have an isolation txfmr.

3 phase wye configuration is 208 between hots and any hot to neutral is 120.

Good marinas are upgrading to transformer systems so it can have 125/250 in 180 degree single phase. Cheap owners are not doing this and their power usually sucks.

We design systems for the 125/250 single phase on most boats. Only a few larger ones work on 3 phase and can't take our regular 125,/250 . I have many local marinas with crap power and a few ( the nice ones) with correct 125/250 that works with ELCI breakers.

 

[SKYCHENEY]

With 208 you get 120 to neutral from any of the three legs, but between any 2 of the 3 "hots" you have 208. For most boats, this is not a problem as most don't have any or very few 240v loads. So without an isolation transformer, you get 120 on all of your single breakers and 208 at your dual breakers. But if you do have a transformer things change. There is no neutral from shore so you will never be able to see a hot to neutral of 120v. The transformer is now making the neutral. This means the voltage will be half of whatever you read between two hots on the dock. If you feed 208, you'll get 104v between your hot and neutral on board. So every single pole breaker is feeding 104 and every double pole is feeding 208.

 

[Captain Ralph]

The two, 120 Vac in a single phase does add up to 240Vac Peak to Peak.
Two 120Vac legs from a 3 phase WYE service are 120° apart and when measuring them peek to peek, only provides 208 Vac.

Your ships transformers can help re-shape the distorted AC wave a bit.
Some transformers can boost this 208 to 240Vac also, however loosing some amps in doing so.

For those with out transformers, 208Vac offers a lot of current (un-modified) and most 240Vac equipment can start and run just fine down to 200 VAc.


Lots more reading can be found here;
https://en.wikipedia.org/wiki/Three-phase_electric_power

 

[madhatter1]

Power to docks is single phase with 2 hots, a neutral, and a ground. At a 50 amp with 120 to neutral you can also have 208 between the hots. Not trying to argue, just saying. When I get to Clearwater I will meter and report back. Very curious.

 

[SKYCHENEY]

Power to docks is single phase with 2 hots, a neutral, and a ground. At a 50 amp with 120 to neutral you can also have 208 between the hots. Not trying to argue, just saying. When I get to Clearwater I will meter and report back. Very curious.

That's correct. The 208 has three hots but only two will be wired to each plug on the dock.