Simran THG-750T Step Up & Down Voltage Transformer Converter for 110V & 220/240V 750W

update 2024-06-10We've been using this for three years for several hours every morning with our Italian espresso machine (1800W). It works perfectly, and only gets slightly warm, which is a feature of (1) a well-made transformer, and (2) using appliances requiring less than half of the transformer's rated power. When we're done with the coffee machine, I unplug it. But once, I left it and the coffee machine on all night. It didn't get dangerously hot (not even close), but when you leave things like this on for that long, you risk damaging them. I feel that this unit would tolerate that, but choose not to test it, because let's face it: it's a consumer product, not industrial or military, not designed for full-power continuous use, and doesn't have the margins for that usage.I'd like to mention one additional positive point (and add a star to my review): the output socket (shown incorrectly in the current photo) is in fact a universal model that will accept plugs from the US, UK, France, Germany, Italy, and many other countries without an additional adapter. And it comes with a fuse in case you blew the replaceable one by using it with something that required too much power.========================original review 2021-02-19I've only been using it one day in step-up mode (the 5000VA reversible model), but tested it with a 2100W hair dryer, an 1800W espresso machine, and an 1800W ice cream maker. It worked flawlessly on all of them and barely got warm. When you're going to be using a transformer for extended periods with high-power loads, it's important to get one large enough - twice the power of your intended use is by no means too much. It's got a ton of iron and does the job with ease. That's the good news.Most of the negative reviews that I've seen are due to users not understanding how step-up and step-down transformers work and how they should be used. It's not really as simple as just plugging stuff in. There are several areas that may prove difficult:1. Depending on your specific use case, grounding may not be present with the supplied adapter.2. Output voltage in step-down use can be dangerous, and could require rewiring the wall socket.3. No way to adjust for high or low input voltages - some situations may just not work.4. Line frequencies aren't converted by this (or any) transformer (not a fault of this transformer).1. Regarding grounding: when using it in step-up mode, the European "Schuko" plug (used in France and Germany, for example) has a ground, but only if plugged into a socket with the proper ground connector. The small adapter supplied is ungrounded two-pin only, and doesn't carry ground to the transformer through the Schuko plug. You'll need a different adapter if you want ground, such as https://www.amazon.com/gp/product/B007KLU07U/. And there's a similar problem on the output side: Schuko plugs don't have a protruding ground pin, so you'll need the same kind of adapter to carry the ground to your appliance. The plugs used in the UK, Italy, China, and many other countries have ground pins that protrude from the plug, and these will all carry ground to the appliance. It would've been a good idea to include at least one of these adapters with the transformer for use in step-up mode instead of the two-pin adapter that was supplied.2. The next point is that this is an "auto transformer": the primary and secondary aren't isolated, they're on the same coil. Without going into the electrical detail, it means that when using it for step-down, depending on how it's connected to your 230VAC mains, the voltages on the pins of the output socket will be either neutral and 115V, or 115V and 230V, and you can't tell which you've got without a measurement device. If you're unlucky enough for it to be configured in the latter combination, your appliance will appear to work fine, but may be dangerous. A defect in the appliance (and many have such defects) could allow 230V to come in contact with the surface, which can easily kill you. When used as a step-up, the situation is similar, except that there are no dangerous configurations: the output pins will be either neutral and 240V, or 120V and 120V-opposite-phase (resulting in 240V across the two pins). These are both safe, because appliances designed for 220-240V can be safely connected either way, since sockets aren't polarized into neutral and hot as they are in North America. To summarize this point: you need to understand how an auto-transformer works in step-down mode and measure the voltages at the output socket with a meter, or you risk electrocution. If you see 230V on either output pin (measured to ground), reverse the direction in which the plug is inserted in the 230V socket, if you can. If you can't, you should have the socket rewired to reverse the connections to the two non-ground pins.3. The next point is that there's no way to handle voltage variations with this transformer. In N.America, current practice considers "nominal" AC to be 120V, but in practice can be anywhere from 110V to 120V (legally as high as 126V). The resulting output voltage can therefore be anywhere from 220V to 240V or even 252V. This may be too high for some appliances: nominal voltage in most of Western Europe is 230V. Many transformers provide a way to adjust for high US input voltage, but this one doesn't.4. Finally, another point to be aware of, which is not a weakness of this particular transformer, is the difference in line frequencies: N.America uses 60Hz, while most of the rest of the world uses 50Hz. This will cause many clocks (on microwave ovens, for example) to run too fast or too slowly. More importantly, it may cause large motors in N.American appliances (washers, dryers, refrigerators, air conditioners, vacuum cleaners, but even some hair dryers) to run too hot, shortening their useful life significantly. Again, this is not a problem of this transformer, but rather of any attempt to run devices on different frequencies.Once you've dealt with the four areas described above, you should find that this transformer does exactly what it should (which converts voltage, but not line frequency). If you didn't understand or don't feel competent to address all of those areas, you should find someone who does understand them to help you to set it up.

Bought it for use in Ghana to step down from 220 to 110 for the entire house and it works fine. Only issue is that as you increase the load on it, the noise of the step-down also increases, as well as the unit becomes really hot.

I wish this thing had an on/off switch. I have a nespresso plugged into it and it seems like it pulls just a bit of power constantly. I wish, like a surge protector, you could kill the juice completely when it wasn't needed and just hit a switch to turn it back on instead of plugging-unplugging all the time. Still, does what it's supposed to. Heavy duty (or at least heavy), and I've had no issues.

Everything was fine.

recepticle on unit was not very heavy duty, I would be cautious about higher amp loads running thru outlet...I am probably going to modify switching out the outlet....This is an auto transformer not an isolating transformer.......

I recently purchased three transformers including this 3000W Simran unit. Being an Electrical Engineer I tested all three out before plugging any equipment into them. This Simran transformer was miswired, with the hot and neutral leads reversed on the input, and a poor ground connection. Thus the hot and neutral are also reversed on the output when in pass through. Stepping up from 110 to 220V gives you 220V across the two output lines, but each has 110V to ground, similar to US split phase 220. Even worse, stepping down from 220V to 110V gives you 110V from hot to ground, and 110V from hot to neutral, but neutral has 220V to ground! The ground connection from the input to the output was made through one of the mounting bolts, but isolation washers were used and the case is painted, so there was about 8kohms between the ground pins on the input and output, and the case was essentially floating. I can excuse the mis-wiring as bad quality control, but the grounding is simply a bad design.It was trivial for me to reverse the wiring and kluge a solid ground, and now it seems like a decent transformer for my purposes. However, I would strongly discourage everyone from purchasing this line of Simran transformers due to the poor grounding. Poor quality control seems to be the norm for all manufacturers of cheap transformers on Amazon, so I would not recommend that you buy any other cheap transformer on Amazon if you don't follow what I described above and feel comfortable enough with a multimeter to test the transformer before use.

I purchased it to take abroad to use on US voltage equipment. I like the idea that it both step up and step down. I appreciate the prompt service from the vendor. I have not used it yet but I don't expect any problems. On second thought, I should have also ordered one that is less wattage and perhaps lighter in weight.

Worked just fine for my sewing machine digital motor. There were many people suggesting that you order one that is rated at twice the power you will need, but that is just to help with the initial inrush current some devices pull when powered on. Its best to know your device. My motor is rated for 850 watts and does not pull more than that at any point.