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230v 50hz -> DC -> inverter -> 120v 60hz ?

Ok, this is a weird one. I'm in the midst of shipping all my stuff in a container to a South American country with 230v 50hz power. I have more than enough room in the container and want to take my Hitachi 35" TV with me.

I know the TV won't pick up anything over the air, but I've got a Samsung VCR that will receive local TV off air and do the conversion on the fly to something the TV will like better. Also own a whole bunch of DVD's and a player that will work with the TV just fine. In an ideal world where money was no object I'd replace the TV - but I won't get all that much for it here and a new one of similar size down there is darned expensive compared to what I paid here.

The owner's manual explicitly says don't connect it to a 50hz AC power source. Ok, so a plain-old transformer is out. I don't want to risk frying it.

So here's my plan. I'm looking for any responses, ranging from "You'll burn the house down" to "It'll work" or anything in between. "There's a better approach" might be welcome too. ;) Please respond to the group.

The TV draws 205 watts. To run it for a reasonable length of time - worst case lets say its on for six hours during a day and my inverter is 100% efficient I need 112.75 amp-hours of battery capacity - or in the real world about 225 amp-hours, right? I don't want to have to source gel-cell batteries though and I don't want to keep track of charge-discharge cycles.

Large capacity DC power supplies are expensive - except the computer ones. I found a simple hack that allows an ATX power supply to think its connected to a motherboard and turn on, and a 600W ATX power supply runs about fifty bucks - or way cheaper than the batteries and the charger. I'd ideally like to have a 1500 watt inverter - if I wire the power supplies in parallel do I need diodes to prevent backfeed? Is it advisable at all? Might one power supply be adequate? I'm envisioning that the computer power supply would be set to the 230V setting, I'd connect the ATX's 12v+ to the 12v+ on the inverter and the 12v- lead on the ATX to the 12v- on the inverter. If you're not familiar with ATX power supplies or their pinout see this website:

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I know I have to have a fuse on one of the leads too. I'm frankly not sure how to size it. I think I need to make it as small as the smallest-rated link in the chain, which would be 12v at 600W, right?

Thanks for any assistance anyone's willing to provide with this. -Tim

Reply to
Tim
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Wow, did some googling, I am sure you already did. Did find one 230 50 to

120 60. Just a WAG, your not into $12 k and 3 months wait for it.

Diving down out of the sun.

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Ya probably already been there Has some interesting tables on time vs. load

I did read on one site that said they recommended 4-5 times capacity with a TV because of the in rush.

I would not connect the power supplies in parallel. Your going to be pissed when it does not perform as needed. Third world country and all. I went to rural Mexico for 3 weeks on a job and just wanted music. I did not take enough batteries. Stupid me should have thought about rechargeable. There was not a AA to be found until I got back to the airport.

Have fun and try it BEFORE you leave.

Reply to
SQLit

smallest-rated

I just had a brain fart. Call the manufacture and see if you can change the power supply in the TV to 230-50. Manufactures send stuff all over the world I'll bet you can by a transformer and just change it out. No inverter no hassles, maybe like I said brain fart.

Reply to
SQLit

Yeah, in the country where I'm going you can buy an entire farm for $12k. ;) Not really an option.

Reply to
Tim

If you're trying to do this on the cheap, I think I would suggest a sine wave power inverter for electronics and a modified sine wave inverter for the heavier loads. After you get there, buy a 12 volt deep cycle battery and a charger/maintainer. Both of these devices could be connected to the battery at the same time. With the battery in the loop, the charger would only have to produce a few amps and the inverter would have all the power it needs for starting motors and the like. Another thing you could do is buy a generator here in the states and an electric motor down there. Connect the two together with a belt and you're in business. :-)

Robert

Reply to
Robert Calvert

An electric motor is out of the question. I have cats. :) I don't want to build an enclosure. It's enough they don't chew the cables much less having a genset, motor and (chewable) belts!!

The only item I *need* to power off 60hz power is the 205w TV. I don't really want the exact sine-wave inverter bcs. its EXPENSIVE. Assuming the TV is happy with modified-sine, is it valid to have a large-ish locally sourced 12v deep-cycle battery connected with the locally-sourced charger and then the inverter?? Would one wire everything in parallel?

THANKS!!!

smallest-rated

Reply to
Tim

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