Review on 3000 Watt Heavy Duty Voltage Converter Transformer - Step Up/Down Power Converter with Circuit Breaker Protection – AC 110V/120V/220V/240V – DC 5V USB Port - CE Certified - 3-Year Warranty by Edward Mcnamara

I bought two 500 watt versions of this transformer to convert the voltage from 230 V from the mains to 110 to reduce / 120 V for use with US devices abroad. The Transformers appear to be well built, although one of them arrived slightly damaged (the case was bent on one side, probably because it had been dropped or hit something during shipping). As some other reviewers point out, they smell chemical upon unboxing. Based on the manufacturer's response to another review, it's likely some sort of thermal paste or gel applied to the product for operational reasons. I personally don't think the smell is overpowering and I don't notice it more than a few inches from the product. The pins on the US plug were slightly bent inwards, but that was easy to fix and I was able to plug it into the Shucko 2-pin adapter that came with it. There is a plug on the back of the transformer. /fuse that you connect to the correct input voltage for your region. External voltage options 240V, 220V or 200V; no option for 230V input. I started with 240V first to see how it would work. I connected the transformer and turned it on with the switch on the front of the transformer. Measured with a digital multimeter with an input voltage of 230 V and an input voltage of 240 V selected on the back of the device, the output voltage was approx. 105 V - too little. I disconnected the transformer and switched to 220V input voltage; This gave me an output voltage of about 110V - good. Based on this conclusion, I recommend that you ensure that the output voltage meets your expectations before connecting anything expensive to this device. Seriously, DO NOT plug in a 120V surge protector or any other sensitive device. electrical polarity into the step-down transformer 220 without first verifying that the output polarity is correct. The principle of operation of an autotransformer is that the current energized (or hot) from an outlet is reduced to 110/120; The neutral wire goes straight through the transformer since there *should* be no voltage on the neutral wire. The problem is that most European countries don't use polarized plugs, which means you have a 50/50 chance of correctly plugging the transformer into the socket. If you wire it backwards and the phase and neutral are reversed, the output side (transformer 120V out) will have 120V line (hot) and 220V neutral. In most cases this is not a problem as the voltage (potential difference) is still 110V. However, this can cause serious problems with surge protectors and other reverse polarity sensitive devices. Make sure you buy a transformer with the right wattage for what you intend to use it with. Allow sufficient margin between the wattage of your device and the specified wattage of the transformer. The transformers have been in continuous use since they were received and have worked well so far. For the price they seem to be excellent value for money. I will update my review if anything changes.