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Old 12-02-2007, 05:33   #16
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The manual had it buried away but in one place it did state that the output voltage and frequency was the same as the input voltage / frequency.

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Old 12-02-2007, 08:05   #17
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Originally Posted by Whimsical
Not visa versa
It is just an inverter where the input range is 90 - 255 volts. I presume auto ranging, and the output can be either 110 or 220v. Output frequency can be either 50 or 60 hz and would be independent of the input frequency.
Sounds like the ideal solution for a cruiser. Buy the output that suits the installed appliances and plug it in anywhere.

Switch mode just means a type of power supply that uses dc, or rectified ac, which is switched on and off at a high rate, typically 20 khz.This is stepped up or down through a small ferrite transformer to what is required. If the device has a dc output the quazie ac is rectified and filtered. If it is an inverter the input switching is done to create an output that is more sineusoidal in shape. This is then filtered to become a true sinewave. The squarewave or semi sinewave inverters don't control the input properly nor are they filtered well so the output in rougher. The high frequency allows the use of small and light weight transformers.
All dc to dc, ac to dc and inverters are basically small variations on the same theme.

The output can be fully isolated from the input so it would act as a traditional transformer in regards to galavanic isolation as well. Seems an ideal solution except for susceptability to lightning that a traditional tranny would better handle.

If you're referring to the Mastervolt switching isolation transformer, es101 is right, buried in the manual it says it puts out the same voltage as goes in. I'm kind of surprised at this because I assumed it would have been easy to make a switcher that is autoranging input, maybe even switch selectable output.

If you are refering to the Victron that was in the quoted section of your post, that is just a regular isolation transformer that is center tapped on both the primary and secondary coils, so four choices exist, 120-120, 120-240, 240-240, 240-120.


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Old 12-02-2007, 16:07   #18
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OOPS Must have been asleep.
I was refering to the mastervolt and didn't go back to check john's link.

Looking at the introduction I made assumptions, stupid thing to do. The manual does indeed state the output tracks the input. To make it do this would add complexity and cost only to remove functionality. Being marketed as a galvanic isolator it is obviously aimed at the boating fraternity. To make the output track is absurd and I sent an email to mastervolt asking about it, copy below.

The manual for the MASS Galvanic isolator states that the output voltage tracks the input voltage and frequency.
I would have thought that a fixed or selectable output would be more appropriate. By mimicing the input it does perform isolation but does nothing to address the problem of different input voltages and frequencies of the installed appliances when used with a different input.
This is a common problem for the cruising boat community.
I am making the assumption that this device is a switch mode device similar to an inverter. If this is so I would think fixed or selectable output characteristics would be more appealing to a broader range of marine customers.
Do you have a product that does offer what I require.
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Old 12-02-2007, 16:39   #19
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Good letter Mike,

Let us know what the response is.

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Old 12-02-2007, 16:54   #20
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Thank you, Mike. Couldn't have said it better. Please let us know what they say.

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Old 20-06-2007, 03:05   #21
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This is a guide to some important issues when deciding to use your electrical appliances in another country. It includes a table describing electrical systems worldwide, illustrations of electrical plugs you may run across, advice on using your computer and other general advice that you may find helpful. Finally, there is a list of sources for electrical travel accessories.
World Electric Power Guide
Electricity Around the World

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