I have a Mac computer that a friend of mine built for me years ago. I can’t get a hold of him, and I love the computer and am taking it to Thailand with me.

I’m very worried about the power supply accepting Thailand’s 240v. I’ve been to Thailand numerous times and have gotten used to looking for the “110-240” to make sure stuff will work over there. The computer has been different though.

I can barely make out on the back of the computer where you actually plug the power cord into the psu the writing:

15A 125v~

10A 250v~

Does that mean it’ll assuredly work in Thailand without problem? I could also see through the grill encasing of the Mac “delta electronics” if that helps. I tried to get in there further but didn’t want to take it apart too much more.

Thanks for any help with this. I wasn’t sure where else to go to get reliable information.

 

Hello,

The numbers on the plug will not say anything about the voltage of the powersupply.
It is just the safe region of the plug itself.
You will need to know more about the powersupply itself.
Some will have a switch for selecting 120 - 240 Volts.
Others (like the newer laptop adapters) will have a working range of 90 - 240 Volts.
Be sure what kind of powersupply is used before plugging in.

Bertus

 

If you have a schematic of the power supply that you can post that might be all we need.

If it turns out that the supply only runs from 220/240 you will find stepdown transformers easy to find and not too expensive.

What part of Thailand?

 

Take some photos of the mains input, is there a Dual voltage selection switch ?

 

Thank you for the replies. I realize the photos may not be the most helpful, I just don’t feel comfortable taking it apart any further, but I may have to.

I don’t see a switch but I can’t access the entire unit so it’s hard to tell.

I will be in Bangkok.

 

One last clue that may not even help, I can also see through the back grill the “delta electronics” and the tag has has writing “15GENW3H-1”.

Is there any other way find out this information without removing the power supply?

 

Now, through the back grill I can see a yellow thing that says 250v~.

 

That's a capacitor, looks like your psu is fixed at 120V..

 

I concur with Dodgydave that a 250V cap strongly suggests 120 VAC input.

You might consider just planning for a step-down transformer as the default solution.

Bangkok is pretty good -there are plenty of electronics parts distributors/sellers around the city. Let me know if you have any difficulty finding some for your needs.

 

I have a Mac computer that a friend of mine built for me years ago. I can’t get a hold of him, and I love the computer and am taking it to Thailand with me.

I’m very worried about the power supply accepting Thailand’s 240v. I’ve been to Thailand numerous times and have gotten used to looking for the “110-240” to make sure stuff will work over there. The computer has been different though.

I can barely make out on the back of the computer where you actually plug the power cord into the psu the writing:

15A 125v~

10A 250v~

Does that mean it’ll assuredly work in Thailand without problem? I could also see through the grill encasing of the Mac “delta electronics” if that helps. I tried to get in there further but didn’t want to take it apart too much more.

Thanks for any help with this. I wasn’t sure where else to go to get reliable information.

Some power supplies are basically for 220V, but have the option of a voltage doubling rectifier that you can identify by the series pair of reservoir electrolytics. Usually they have a moveble link that connects the junction between the 2 caps to an AC arm of the bridge rectifier. There is a parking pin for when the supply is 220V - leaving it connected for doubling will go bang if the supply is in the upper range. Some have an automatic voltage detect, discrete component types with a power triac are common, but integrated types that may or may not include the triac exist.

Later types of PFC front end have a wide voltage range good for anywhere, earlier ones may not. some PFC is just a dirty great choke in series with the mains input - see notes above.

Check the voltage rating of the reservoir caps, its likely to be 200V or 400V which is clear enough. a series pair of 200V is also obvious - but check the doubler link. 450V probably means PFC front end - but don't just assume the PSU can handle 220V.

 

It looks like everything Delta currently sells in this area is compatible with both voltages. Your number is not one of their model numbers but you might consider just asking them. Or dig in a little farther so that you can read the actual model number.

 

Thanks to all for your responses!

I think the best thing to do is buy the step down transformer since it would be a big loss if I plugged it in and fried it.

 

I concur with Dodgydave that a 250V cap strongly suggests 120 VAC input.

You might consider just planning for a step-down transformer as the default solution.

Bangkok is pretty good -there are plenty of electronics parts distributors/sellers around the city. Let me know if you have any difficulty finding some for your needs.

I take it that it would be better to buy it in the states? If so I’ll just pick one up because I’ll be here for the next couple of days. Thank you.

 

I remember the prices at the dealers seemed reasonable and they were easy to find. Depending upon your situation when bringing gear for the U.S. weight may be an important consideration. I was always right at the limit. Did not bring over any heavy things like transformers.

 

Thanks to all for your responses!

I think the best thing to do is buy the step down transformer since it would be a big loss if I plugged it in and fried it.

Actually; they tend to go bang very instantly and sometimes the damage is surprisingly little.

Doesn't mean you should try it though!

 

Thanks again for all the replies. I am actually in Bangkok now. The computer made it and I followed Dick’s advice to pick up the transformer here, but I realized I don’t know what wattage I’d be safe with going with.

It’s just a very standard Mac tower, so is there a wattage you all would suggest i go with to be safe on the transformer?

 

Thanks again for all the replies. I am actually in Bangkok now. The computer made it and I followed Dick’s advice to pick up the transformer here, but I realized I don’t know what wattage I’d be safe with going with.

It’s just a very standard Mac tower, so is there a wattage you all would suggest i go with to be safe on the transformer?

Get a big one and you'll be fine (1500W).

 

I think GopherT's advice is probably well suited to your situation.

To be a little more certain, you will have to find out how much current your computer takes. One way is to read it off of the power supply's nameplate and another way is to measure it with a true RMS ammeter.

Once you have determined the current multiply it by 240V to get the wattage rating (technically the VA rating) you need and get something significantly larger tor some margin.

Amorn Electronics (Bahnmo and Fotune Plaza among other locations) usually has a good assortment of step-down transformers.

 

I just read the thread and I would have just swapped out the computer power supply with a dual voltage model. Bet its cheaper by a long shot.

 

I just read the thread and I would have just swapped out the computer power supply with a dual voltage model. Bet its cheaper by a long shot.

As long as a reasonably ATX power supply was used, I would agree. It would also keep his desk area a bit more tidy and his life simple.