C-Power Iso Transformers

GSL

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My 2002 SeaRay 460 Sundancer was built for the European market, it is a 220 volt boat, and was fitted with two C-Power Iso Transformers of 7.5 kva each.

Every time the pontoon power goes down, which happens quite often in Spain, when the power comes back on, the initial load that the Transformers take trips the pontoon power out, and if I am not on the boat, it then has no battery chargers running until next time I arrive, which can be a month or two.

When returning from a trip out, in order to plug back into shore power, I must go into the engine room, turn off the mains in switch, turn off the two power lines and everything else on the DB Board, and then plug in, otherwise it trips two different pontoon circuits on the pontoon.

Once plugged in, I have to turn everything else on in the correct order to prevent further trips.

According to the Q & A section of the C-Power website, this is called an inrush problem and recommends a soft start system, why would you not fit one at the build time if it was an issue???

I have already removed one of the Iso units, given that the Genset only supplies 6 kva I could not see the problem. Everything still runs fine but the tripping problem still exists.

I don't really want to fit a soft start system into the circuit, (expense) and wonder if it is a big deal to remove the second Iso unit altogether. Is there a big downside? I do know it takes up a lot of space in the engine room, and they weigh plenty. No other boats in my marina have these fitted that I am aware of.

Thoughts appreciated.


Graham
 

rafiki_

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What are the transformers for? The galvanic isolator is to stop stray currents making a circuit through the anodes, through the boat, to the shorepower. Do your transformers do the same, or are they in the circuit to smooth out spikes?
 

GSL

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What are the transformers for? The galvanic isolator is to stop stray currents making a circuit through the anodes, through the boat, to the shorepower. Do your transformers do the same, or are they in the circuit to smooth out spikes?

My understanding is that they are fitted to both prevent spikes in the power supply and to do the same job as galvanic isolators.

The more research I have done the more reference I see to them needing a soft-start device in the supply line.

GL
 

Seastoke

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do you know what type of circuit breaker is fitted where it trips ,its not the size ie its proberbly 16 amp but in genrall there are three three types of breaker ,B,C,D, B b is normally for domestic c is for commercial and industrial, and is for special machinery ie transformers you could ask if it could be changed , if you change the design of your boat could it not affect the insurance.just trying to help
 

rafiki_

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My understanding is that they are fitted to both prevent spikes in the power supply and to do the same job as galvanic isolators.

The more research I have done the more reference I see to them needing a soft-start device in the supply line.

GL

To my understanding, galvanic idolaters do not manage power spikes from the shorepower, but mainly eliminate the low power stray currents that eat through the anodes.
 

jfm

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There must be something else wrong. I have iso transformers (2 of them, 125amps per shoreline and I often plug into an undersize - 60 amp or 90amp - shore supply) and never have this problem. To my knowledge I don't have a soft start device. I don't know how such a device would be made. (I have soft starts on several large motors but that's something different altogether, I think)

If the problem wont go away then removing the iso transformers altogether and fitting a galvanic system would be ok
 

GSL

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Appreciate your thoughts JFM

Here is a link to the soft start that has been suggested might solve the problem, but I am really wondering why bother.

http://www.aquafax.co.uk/html/product_details.asp?ID=22227

The space these units take up in a 50 foot boat is a hassle during servicing, and given no other boat at SCM have them that I am aware of, will I be any worse off if removed.

GL
 

jfm

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Hmm yes Mastervolt do go on at length on their website about these soft start things. They do one for my transformers here http://www.mastervolt.com/products/soft-start-transfer-systems/soft-start-22-kva/ but i'm pretty sure I don't have them installed. Wouldn't swear to that though!

Anyways, I agree with you that just getting rid of both iso transformers, not buying a soft start, and fitting a galvanic protector instead, probably makes the most sense. The alternative of 2 x iso and 2x soft starts burns up a heck of a lot of space on your boat!
 

Cruless

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try plugging into a different electricicty pontoon supply and see if you have the same problem, the transformers do have a large inrush of current when first plugged in,
A, it could be just a weak circuit breaker on your pontoon post that needs replacing
B as already said a type C CIRCUIT BREAKER would solve the tripping problem
C personally id go with jfm`s suggestion and remove the lot and install a galvanic isolator.
 

GSL

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try plugging into a different electricicty pontoon supply and see if you have the same problem, the transformers do have a large inrush of current when first plugged in,
A, it could be just a weak circuit breaker on your pontoon post that needs replacing
B as already said a type C CIRCUIT BREAKER would solve the tripping problem
C personally id go with jfm`s suggestion and remove the lot and install a galvanic isolator.

Don't think changing power point on the pontoon would help, it even did it when we came back from the sea trial when I bought the boat in Porta Baneus, I just did not realise at the time that there was an issue.

Graham
 

kashurst

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I´ve just been looking up transformer soft start devices. Theres not much to them, all they are is a resistor in the supply line with either a relay contact across it or the semiconductor equivalent, with 1 or 2 seconds delay that then by passes the resistor. So the initial inrush current is limited whilst a magnetic field is created inside the transformer.
Quite why they want so much money for them is beyone me as there is about 20 quid of bits in there including the posh box. I suspect JFM may well have them intergrated in his transformers.

If space is an issue I would still bin them. If you use a galvanic isolator make sure your have residual current detectors in the boat mains circuit. (you almost certainly will have one at the switch/breaker panel.)
 
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