Voltage Booster

[Freestyle]

My yacht club managed to build an entirely new marina to third world electrical standards. A year ago with much fanfare they took delivery of the new marina. It only took a few burned AC units before I realized they were getting less than 200 volts. This problem was investigated and after much ado they discovered the contractor had used 208 volt transformers.

I shipped off to a nearby club waiting for them to replace the 208 volt transformers with 240 volt transformers. Today they announced the new transformers were in only it turns out they had contracted for 220 volt transformers and that is what we are going to have. My guess is a fire is only a matter of time in the making.

One suggestion given to me was to buy a voltage booster. The Marlows all have them and they are made by Charles Inc. I assume they trade amps for volts which is probably manageable.

Anyone familiar with voltage boosters, costs, effectiveness, etc.

Thanks

Bruce
Freestyle
1986 62 CPMY (54 MY with 8 foot extension)
Tampa

 

[Scarlett]

220 volts should be plenty for your ac units if your boat is built to US electrical standards. 208 is where the problems start with ac units. To answer your question about the Charles equipment, there stuff is first rate. John

 

[krush]

240VAC is the nominal standard, but it's a given that +/-10% is completely acceptable.

 

[doc g]

You have transformers onboard , I believe . If they are not wired to boost they usually can be just by switching out the input taps. Mine have switches . But you can hard wire them to boost if they don't have switches. If you hard wire they will boost even if you have correct voltage. If you only use the 220 at the YC and never use anyone else's dock power this may be ok, if not have an electrician wire up some switches so you can select the input voltage.....Pat

 

[carolinacoast]

Perhaps a Charles isolation transformer can be added to your existing ones to make sure that it will be automatic boosted.

You will want a fully automatic bulletproof system. Agree that Charles is very reputable.

Likely that you will want to have 2 cords plugged in to make sure you have enough amps when guests are aboard.

Would recommend a marine electrician make sure that you will end up with a system that complies with ABYC standards, in case someone's insurance has to pay for something later.

 

[Boatsb]

240VAC is the nominal standard, but it's a given that +/-10% is completely acceptable.

Krush 240 x .9 = 216

By the way i believe the standard is 117 or 234.

Now if they contracted for 220 volts from the power pole that's different than 220 from the 208.

One is down and one is up.



Usually the 220 and 240 are interchangeable in discussions.

 

[SKYCHENEY]

I agree that 220v will be just fine. The problem is that if you have 220v at the shore transformer, you may get much less on the boat. It depends on conductor size and length of run and how much load is on there. So, if you are on the end of the dock and everyone is running their A/C on the hottest day of the year, you may get less than 216v. You'll just have to try it and see what you get.

As stated, you do already have transformers on the boat and they are capable of boosting the voltage by 15% if rewired to do so. I rewired mine with switches to boost and I use them occasionally but I don't need to boost at my home slip.

You could boost 220v to 253v with the transformer switches. This is within acceptable range and will be more efficient than using the lower voltage. However, there is no free lunch and the total amp load on your power cord is still limited to 50 amps. Your input is still at 220v so when boosted, your ammeter will read 15% less than the total amp load on the cord.

 

[Pete]

My read of the situation is three separate items to understand.

First, check the specification plates on your Cruisair units which are mounted on the control box of each compressor unit, and verify your your spec. I believe you will see "230" volts" which is the base number for determining the lowest safe operational voltage. If your base is 230 then 207 is your low end specification.

Second, the problem that resulted in using 220 volt transformers instead of 120/240 is that the wiring from the transformers out to the docks is incapable of being used for single phase 120/240 volt distribution. It takes additional "common" distribution wires to go to single phase.

Third, the line drop in the distribution system seems excessive for a 2017 electric code. Bottom line, I suggest your club get the local electrical inspector out to do a comprehensive look at the system with emphasis on the gauge of wire used throughout the system, starting at the utility feed line.

Pete

 

[Freestyle]

Can someone walk me through how to get 240 out of wiring my transformers differently? It sounds like an inexpensive solution and with a switch that I just change when leaving my home slip for a trip.

Pictures and diagrams would help too.

Thanks

Bruce

Freestyle
1986 62 CPMY (54 with 8 foot extension)
Tampa

 

[SKYCHENEY]

Diagram can be found in this thread:

http://www.samsmarine.com/forums/sh...ion-transformer-switches.&highlight=isolation

I've done several of these. Questions? Ask away.