2000 Watt Voltage Converter Transformer - Heavy Duty Step Up/Down AC 110V/120V/220V/240V Power Converter - Circuit Breaker Protection – DC 5V USB Port - CE Certified [3-Year Warranty]

Ordered this 500 Watt transformer to use an appliance from Korea in the U.S.A. Per the manufacturer, I computed the amount of wattage needed for the appliance and then doubled it. So for example, I computed that my appliance required 210 watts, so I doubled to 420 and rounded up. The appliance I have (from Korea) didn't specify the wattage using "Watt" or "W", but instead said "VA". I believe this is the same or equivalent, but you should check with a qualified electrician if this is the case with your appliance. If your unit shows just Amp or Voltage, you can multiply the two to arrive at Wattage. Again, check with someone who is qualified before using the appliance or ordering a unit so you can ensure you get the correct wattage. My calculations worked well and the appliance has functioned without problems under constant load the entire time without issues at the selected wattage. My understanding is that you'll want to double the wattage due to changes in the flow of electricity and the appliance's peak demands that could exceed the normal wattage used or identified on the back of the appliance. Be careful for laser printers or microwaves (and other high wattage appliances), I believe that can have peak watt use of much greater than their rated wattage. I believe the rule of thumb is to multiply by 3 instead of 2 to arrive at the wattage of transformer you will need. If you live in a country that has inconsistent power delivery, you may consider purchasing a separate unit that regulates the voltage. Some transformers have this built in, but this one does not. If you will be using this transformer in the U.S.A. on a modern electrical circuit, you probably do not need a regulator. I did not purchase one and have had no trouble in the month of so that I've used the unit.The transformer does get warm to the touch, but does not get hot. I expect to unplug and turn off this transformer during vacations and while away from the home for a long period of time, but I believe that this should function well under constant load indefinitely. When you plug in, make sure you select the correct voltage on the back as the removable plug should represent the SOURCE voltage of the electricity that you will be plugging the transformer INTO. In my case, I was using a 220V appliance in the U.S.A. (110V) so I selected 110V on the back and plugged the appliance into the 220V plug on the front. For some reason, I found this a bit confusing so make sure you read the instructions included with the unit.This transformer comes with a quality plug converted for U.S. style plugs (110V) to the European/Asian style (220V) which is useful if you travel internationally and have a dual 110/220V appliance (like cell phones, laptops, etc.). It may come in helpful if you need to convert plugs for the appliance you'll be using with the transformer. In general, the unit feels like it's well made and will be able to withstand a long period of consistent use. The transformer I received was cosmetically damaged during shipment (one corner bent and a few scratches). However I'm hiding this transformer behind some kitchen items so it's not a beauty contest. The unit held up well to shipment and I didn't think the scratches and bent corner warranted a return.As far as the value of the unit is concerned, I'm very pleased with the purchase. This unit appears to be quality and will last quite a while. It was less expensive than similar units and was available for delivery with Amazon Prime. The unit includes a 3-year warranty. With this transformer being used under a constant load 24/7 almost every day, I'm comfortable that all the quality issues with the unit should come out in the first 3 years. Overall: good value, quality unit, and fast free delivery with Amazon Prime. Recommended!

I purchased this transformer to power some US power tools in my amateur woodworking workshop in Israel. Even though my hungriest tool (the table saw) takes only 1800VA I decided to go with the 5000W version in order to be safe, as it has a universal motor in it which will draw lots of current when it's stalled, and potentially at startup, so I decided not to take any chances.It comes with a European plug adapter - nice thinking.The only beef I have with this unit is the power cord: it is ridiculously short, approx. a foot or so.Before using it I opened it up to see if there are no loose wires or anything that got damaged during the long trip as some people reported it being dead on arrival or burning up immediately as they plugged it in for the first time. Inside it looked pretty solid, the overall build and soldering was ok. I do wonder if the soldering will hold during prolonged usage at high output power values. Feels like the temperature could melt it.As a considerable amount of people (those that gave this unit 1 star) report it failing after 5-6 months I'm scheduling a routine checkup for this unit every 4 months.I tried it with all of my power tools and I couldn't be happier. Everything works like a charm.If you're using it to downstep (220V to 110V) you absolutely must make sure that the polarity is correct before you proceed using this unit.If you have incorrect polarity what will happen is that you will have 220V between the ground and neutral, which is something you really don't want. Some users have reported this as a problem with the unit not realizing that they are the ones with the problem, and all transformers of this type (autotransformers) would exhibit the same behavior. There are 2 possible causes for you to have reversed polarity - you inserted the plug incorrectly, or you have incorrect wiring in the socket. The plug has 2 upper parallel pins - hot and neutral, and one pin below them in the middle - the ground. The hot must get the 220V and the neutral must get the 0. The problem arises when these 2 pins are reversed.1. Incorrectly inserting the plug: in some European countries the plug can be inserted in 2 ways (fortunately in Israel it's not a problem). If you have one of those you better mark for yourself the correct way to insert the plug, like which way is up.2. Incorrect socket wiring: the electrician switched the hot and the neutral in the socket itself.How do you know if you have reversed polarity? If you have a voltmeter it's easy - you just check that you have either 110V or 0V between any two holes in the output. If you see 220V between the ground and anything else you've got reversed polarity. If you move your transformer to another socket make sure you test it again because the electrician could do a bad job on the new socket.I will continue to update as I use this unit in the coming months.