Dual voltage system?

I may be moving from the US to a country that uses 240V/50Hz electricity. I’m wondering how practical it would be (if I’m installing solar) to setup dual supplies. If I buy a house, it will obviously come with appliances, light fixtures, AC units, etc. that all run on 240/50. And while all my computer equipment is dual voltage, my audio/video gear, power tools, some very nice ceiling fans, and smarthome equipment - all of which I’d prefer not to have to replace - will only run on 120/60.

With 240 volts, it is as easy as plugging a device into an outlet to absolutely ruin a power tool built for 120 volts. Been there. It is often difficult to use transformers: 1) they are heavy (typically the better they are, the heavier they are); 2) many, especially lightweight travel-variety ones, are unreliable and overheat/fail due to various reasons; and 3) they cannot easily be permanently attached to the end of a cord to ensure some ignoramus does not unwittingly plug it in where it oughtn't to be plugged.

Unless these are high-quality, indispensable tools that have no local equivalents available for purchase on the new voltage system, I would recommend exchanging them for 240-volt tools which you can freely use at your own home or in that of a neighbor or friend. Tools do sometimes get loaned out--and will the borrower remember to use the transformer you provide with it? Worth a thought. (A good friend ruined my Ryobi battery charger this way--but unfortunately, with Ryobi I have yet to find a 230-volt equivalent, so I have no choice but to use a transformer--and local tools here in Thailand are no match to Ryobi's quality, so I have indeed wrestled with this very issue.)

Grid-> charge controller -> battery -> inverter -> 120v 60hz equipment.

With 16 years overseas, transformers at each outlet that uses the 120 volts was the answer. I've used them in all sorts of sizes from 20 amp 120 volt on down.

I would let go of anything hardwired such as a ceiling fan. Maybe leave it with family or a friend until your return.
For the rest consider a portable battery based generator that can charge with 230/50 and provide 120/60. Or make your own.
The house itself I would stay with the native voltage etc.

Norwasian said:

With 240 volts, it is as easy as plugging a device into an outlet to absolutely ruin a power tool built for 120 volts.

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But it’s the wrong plug type. I don’t see how I’d ever make that mistake.

Norwasian said:

Been there. It is often difficult to use transformers: 1) they are heavy (typically the better they are, the heavier they are); 2) many, especially lightweight travel-variety ones, are unreliable and overheat/fail due to various reasons; and 3) they cannot easily be permanently attached to the end of a cord to ensure some ignoramus does not unwittingly plug it in where it oughtn't to be plugged.

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I think you misunderstood my question. I’m talking about installing a residential solar system (120/60) and having it run concurrently with the existing 240/50 system. Possibly replacing that with solar (outputting 240/50) in the future. (I don’t know enough about this stuff to know if 1 array of panels can be used to supply 2 charge controllers.

Norwasian said:

Unless these are high-quality, indispensable tools that have no local equivalents available for purchase on the new voltage system, I would recommend exchanging them for 240-volt tools which you can freely use at your own home or in that of a neighbor or friend.

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They are high quality and I’ve spent years collecting them. Sadly, I haven’t used them much thanks to all the demands on my time - but I’ll be retired once we move and I would dearly love to finally get to use them. I suspect they’re replaceable overseas but that’s going to be expensive. (And that’s just the tools; there’s also the home theater system And high end audio gear. You take a beating selling that stuff secondhand.

Norwasian said:

Tools do sometimes get loaned out--

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That’s actually yet another benefit. I’ll have the perfect excuse for saying, “Sorry, no.” And when I tell them the reason, they won’t be irritated or upset with me.

time2roll said:

I would let go of anything hardwired such as a ceiling fan. Maybe leave it with family or a friend until your return.

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The move will be permanent. You’ve brought up a good point, though; if I do run to power a couple ceiling fans, I’ll want to label the wiring that comes through the ceiling to alert people that it’s 110 - not 220.

time2roll said:

For the rest consider a portable battery based generator that can charge with 230/50 and provide 120/60. Or make your own.
The house itself I would stay with the native voltage etc.

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That’s an interesting idea. Probably way cheaper, too. Where would I find plans/info to make my own?

DonnyBahama said:

The move will be permanent. You’ve brought up a good point, though; if I do run to power a couple ceiling fans, I’ll want to label the wiring that comes through the ceiling to alert people that it’s 110 - not 220.

That’s an interesting idea. Probably way cheaper, too. Where would I find plans/info to make my own?

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Three components: Battery, 230v charger, 120v inverter. Make a wooden box with wheels and good to go.
Roll it around for the tools you need. Park it next to the audio/video gear when done working.

Lots of build projects for a portable on this website.

DIYrich said:

Grid-> charge controller -> battery -> inverter -> 120v 60hz equipment.

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That’s exactly what I was thinking. And if we end up building rather than buying a house, I could also do a second controller/battery/inverter to output 240/50. I could even run separate circuits everywhere (ideally using 2 separate colors of romex) and have 120V outlets right next to the 240V outlets. If I wanted to get really anal about it, I could use one color for all 120V outlets and a different color for all the 240s. Then use colored tape at the plug end of each power cord to (hopefully) make it dead obvious that red marked plugs go into red outlets and blue marked plugs go into blue outlets. Probably overkill but definitely the safe way to go. Just have to remember to mark each new electrical item as it comes in the house.

time2roll said:

Three components: Battery, 230v charger, 120v inverter. Make a wooden box with wheels and good to go.
Roll it around for the tools you need. Park it next to the audio/video gear when done working.

Lots of build projects for a portable on this website.

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Thanks!

I would stick with native voltage for everything hardwired.
Separate outlets for the two systems is fine, as long as the correct outlets are used.
The two systems can share the same battery bank, as long as they are the same battery voltage.
Solar panels can not be connected to two different MPPT's. But if the two systems share the same battery bank, either system can charge or draw from the battery bank, simultaneously.

Having hardwire 120v circuits may reduce the resale value of the home.

Near military bases in Korea, many of the houses are hardwired for both with a 120v transformer usually residing in a closet. Always was a bit sketch to me.

Some other older houses were likely wired similarly since Korea went from 120v to 240v (sometime in the 80s I think).

DonnyBahama said:

But it’s the wrong plug type. I don’t see how I’d ever make that mistake.

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Here in Thailand, plugs are made to accept both types. And they are used virtually interchangeably. This is also true of Laos and probably most other countries in Southeast Asia. You may be going elsewhere, in which case this may not apply to you.

Norwasian said:

Here in Thailand, plugs are made to accept both types. And they are used virtually interchangeably. This is also true of Laos and probably most other countries in Southeast Asia. You may be going elsewhere, in which case this may not apply to you.

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Wholly crap, that's just all kinds of unsafe.
They really should follow standards.

Is it cool to have 230/240vac @ 50hz using the same main building ground as 110/120vac @60Hz? What if we add 240vac split phase onto that same ground as well?

You can get torodial step down transformers that plug into 240vac and output 120vac ... I presume they would output @ 50hz

I like the charger -> battery -> inverter idea, then you're virtually making UPS's as well

timselectric said:

Wholly crap, that's just all kinds of unsafe.
They really should follow standards.

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Standards?! Thailand knows little about such niceties. Ground wires are rarely used either--and the "standard" 230-volt plug in Thailand is two prongs only. Many here end up cutting off the ground prong on something like their computer's cord in order to be able to plug it in anywhere. All of the older homes use just two prongs--albeit they are of the versatile type to accept either round prongs or flats. Many homes built in the last decade will have three-prong receptacles, but the ground prong is rarely connected to anything--only two wires are used to connect the receptacle back to the breaker box.

Any distinction between 220-volts and 110-volts would have to be very plainly labeled on both the receptacle (if other than 220) and the plug of the device if a dual-voltage system were considered here. Otherwise, a careless moment of inattention is all it would take to ruin the device permanently.

cs1234 said:

Is it cool to have 230/240vac @ 50hz using the same main building ground as 110/120vac @60Hz? What if we add 240vac split phase onto that same ground as well?

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Yes
Always one grounding system for everything.

Norwasian said:

Here in Thailand, plugs are made to accept both types. And they are used virtually interchangeably. This is also true of Laos and probably most other countries in Southeast Asia. You may be going elsewhere, in which case this may not apply to you.

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timselectric said:

Wholly crap, that's just all kinds of unsafe.
They really should follow standards.

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I remember speaker wire was standard wiring. The amount of wires coming out of transformers was amazing. Seemed to be no standards and self taught, not apprenticed.

This was on the Thai air base barracks that used to be US based during the late 60s and early 70s. It was the same in the villages and towns.

Has this changed?

chrisski said:

I remember speaker wire was standard wiring. The amount of wires coming out of transformers was amazing. Seemed to be no standards and self taught, not apprenticed.

This was on the Thai air base barracks that used to be US based during the late 60s and early 70s. It was the same in the villages and towns.

Has this changed?

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That "speaker wire" as you call it certainly still exists, but is less common now. In Laos it is still quite common. I watched a fair length of it burn up after a week or two of powering a well pump, and, no, I was not the one who installed it! It works great for LED lights--but certain brands of it are highly prone to oxidation/degeneration, and may not conduct current for more than a year.

GFCI breakers are virtually unknown here and hard to find. I have not so much as heard of electrical inspections here--but I think there may be some standards these days for commercial construction like schools which do get inspected by the education department, or hospitals which probably are inspected by the health department, etc.

The massive wire tangles dangling from utility poles have become infamous, and I've heard Bangkok is beginning to transition to underground wires. Hopefully that cleans things up a bit. There are some wonderful (i.e. hilarious and/or pathetic--depending on one's perspective) photos of Thai wiring issues to be found online. I'm amused by the ones that show a utility pole in the middle of a roadway, with the asphalt or concrete carefully packed around it on all sides. (Of course, that's not the only reason Thailand has become #1 among peacetime countries for traffic fatalities.)

The "standard" Thai plug has probably not changed much. Here's a classic example--the first to appear in a Google images search for "Thai electrical outlet":



As can be seen, either round plugs or flat plugs are accommodated easily....but, sorry, no ground prongs. This design is why I am not keen on the dual-voltage idea, besides the fact that I have lost valuable tools to the ease of plugging them in to the wrong voltage (others, not myself, were inattentive to the details...but it matters not who did it, the damage is still done).