Question about shore power frequency issues
I have a 60Hz boat, currently in the Americas. At some point, the boat will
make its way to Australia and other places where shore power is 50Hz.
My question to the group is: What are the good ways to deal with this when at
the dock in a country whose frequency doesn't match that of the boat? I know I
can install an Atlas frequency converter. However, at $18k for 12Kw, I find
myself wondering if there are better alternatives.
Here are the alternatives I can see:
-
Run the genset whenever needed. $18k buys 6,000 hours of fuel at $3/gal and
1gph, but of course there are other costs and issues involved in running the
genset nonstop too. -
Run some sort of inverter-charger setup that can handle 12Kw. Presumably,
this is what the Atlas does, although I'm not sure.
Looking forward to the collective wisdom of the group.
Dan Freedman
Sea Spirit Passagemaker 60
Dan, the approach we are taking on our Nordhavn 47 is to partition inverting
and charging into separate devices and shut off the inverter pass-through
when on 50 Hz power. Currently we have a Xantrex 4000W inverter/charger.
This approach entails:
- Adding two MasterVolt ChargeMaster standalone battery chargers (either
a 100A and a 60A or two 100s). The will charge up to three battery banks
from any kind of AC power -- 45-65 Hz and voltage from 90-265V. We're using
multiple units for redundancy and to get the AGMs charged quickly if the
power is available. - Reconfiguring the Xantrex so that it is no longer used for charging.
Others who have done this have reported better overall performance from the
inverter. In addition, if both of the other chargers fail we have the
Xantrex charging circuitry as a backup. - Turn off the inverter 120V pass-through circuitry when running off 50
Hz shore power. Most inverters have an internal relay that will pass through
"good" power sensed on the AC bus (rather than using the inverter
circuitry). Assuming the Xantrex would even willingly pass through 50 cycle
power (I need to read the manual), we don't want it to as various motors on
the boat will not like it. So where the shore power is 50 Hz, we'll use it
directly only for 240V items that don't care about the frequency (A/C and
water heater). The inverter won't pass through but will draw from the
batteries, which will be charged directly by the shore power.
The cost for this conversion is just the chargers (24V/100A is about $2,400)
and the electrician's rewiring.
There are a few downsides that need examining. The main one is that some of
the 240V appliances, which will see the 50 Hz power, may not like it. That
includes the oven control circuitry and the washer and dryer. Need to look
into this; if it will be a problem those appliances can only be run when the
genset is on. In addition, the inverter must be properly operated so that it
doesn't pass through 50 Hz power. That may require a series of button
presses, but as it will only be necessary when we arrive at a new marina a
checklist should suffice.
When cost and hassle and redundancy are considered, this seemed the best
approach for us. Others may have different ideas, especially if their
appliances are 50 Hz-tolerant.
Every one I've spoken to who had an Atlas complained about reliability and
the amount of space it takes up, but that of course could just have been my
sample. There are other frequency converters besides the Atlas, like this
one:
http://www.50hz.com/Solid/1ph/12KSS6050.html
But I think you'll find that they are all a) huge (that one is 372 lbs.!);
and b) expensive.
/afb
On Fri, Oct 15, 2010 at 2:17 PM, Dan Freedman dan@fsa.ca wrote:
I have a 60Hz boat, currently in the Americas. At some point, the boat
will
make its way to Australia and other places where shore power is 50Hz.
My question to the group is: What are the good ways to deal with this when
at
the dock in a country whose frequency doesn't match that of the boat? I
know I
can install an Atlas frequency converter. However, at $18k for 12Kw, I
find
myself wondering if there are better alternatives.
Here are the alternatives I can see:
- Run the genset whenever needed. $18k buys 6,000 hours of fuel at $3/gal
and
1gph, but of course there are other costs and issues involved in running
the
genset nonstop too.
- Run some sort of inverter-charger setup that can handle 12Kw.
Presumably,
this is what the Atlas does, although I'm not sure.
Looking forward to the collective wisdom of the group.
Dan Freedman
Sea Spirit Passagemaker 60
http://lists.samurai.com/mailman/listinfo/passagemaking-under-power
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Productions.
Dan:
How much inverter capacity do you have?
What most boats do is:
- Power the things that require 60hz power off the inverters
- Power the heavy appliances off of shore power (Air Conditioning,
washer/dryer/stove), OR, do without them except a couple hours a day when
you run the generator
Check the specs on your appliances. There's a good chance that they will run
off 50hz power.
You will need to charge your house bank off a battery charger that is
powered by shore power. Depending on the inverter load, this may be
adequate, or you might need to run the generator a couple hours a day to top
off the batteries.
If you aren't running air conditioning, you may be able to run entirely off
your inverters, with just firing the generator a couple hours a day to do
the laundry, and heat water.
Some important questions:
- Will your battery charger accept 50hz power?
- Will your appliances accept 50hz power?
- Do you need air conditioning?
- Do you have an electric stove, or a gas stove?
- What is your inverter capacity?
- How many amps do you need to run the boat, not counting the heavy
appliances? (I'm including the refrigerators as something that has to run
off the inverters)
My American boat was based in France for several years, so I've been through
this.
-Ken Williams
Nordhavn 68, Sans Souci
-----Original Message-----
From: passagemaking-under-power-bounces@lists.samurai.com
[mailto:passagemaking-under-power-bounces@lists.samurai.com] On Behalf Of
Dan Freedman
Sent: Friday, October 15, 2010 2:18 PM
To: passagemaking-under-power@lists.samurai.com
Subject: [PUP] Question about shore power frequency issues
I have a 60Hz boat, currently in the Americas. At some point, the boat will
make its way to Australia and other places where shore power is 50Hz.
My question to the group is: What are the good ways to deal with this when
at
the dock in a country whose frequency doesn't match that of the boat? I know
I
can install an Atlas frequency converter. However, at $18k for 12Kw, I find
myself wondering if there are better alternatives.
Here are the alternatives I can see:
-
Run the genset whenever needed. $18k buys 6,000 hours of fuel at $3/gal
and
1gph, but of course there are other costs and issues involved in running the
genset nonstop too. -
Run some sort of inverter-charger setup that can handle 12Kw. Presumably,
this is what the Atlas does, although I'm not sure.
Looking forward to the collective wisdom of the group.
Dan Freedman
Sea Spirit Passagemaker 60
http://lists.samurai.com/mailman/listinfo/passagemaking-under-power
To unsubscribe send email to
passagemaking-under-power-request@lists.samurai.com with the word
UNSUBSCRIBE and nothing else in the subject or body of the message.
Passagemaking Under Power and PUP are trademarks of Water World Productions.