LVYUAN Variable Transformer Variable Voltage Regulator, 0-130V Output, 110V-120V Input, (500VA)

Works great. heavy and sturdy construction. I did notice as many others did that the voltage dialed in on the adjustment knob does not match the voltage on the voltmeter. I used a separate voltmeter and verified that the analog meter in this device is accurate. It should be noted that the unit is designed for 110 Volts so if your supply volts is 120 to 125 volts then there will be a disparity between the indicated voltage and the dialed in volts. Nothing to worry about.I am using this device to power an old vaccum tube amplifier that needs 110 volts to prevent frying the tubes with 125 Volts. so happy i got this. :)

I've used STACO variacs for years. I can't afford them for my home lab. I've bought this one to replace my aging hacked together and falling apart 5amp one I shoved into a case.So wanted something new, clean, and not aged out.I've also bought a year ago, a 20A variac.If you were to buy just one, the 10A maybe your best choice for the small price increase, if you feel you'll never need the 20A one.Just cry once.The 20A IS HUGE, and not fun to keep on the bench daily.5amp one is perfect for the majority of my projects.Small/fits on the bench well and used it as a convenient on / off AC switch for the project under test.But again, 10A maybe a better choice to invest in something a little heavier power rating, over the 5amp... if you don't think you'll ever need a 20A version.I know I do use a 20A version, so settled on the 5a for the "daily driver", and the 20A when I need a variac when working on something with higher power requirements.The 5A (and 20A) work just as it should.The panel meter is just a guide, don't use it as an end all.Top scale, doesn't have any relative accuracy, just treat it as a scale.Use an external voltmeter to be sure.I need to test 4 corners.. so need to know where low line drop out is, and I need to test at specified high line.So an external meter, that is accurate is a must for me.That's it for the negatives.I use the 5a daily along with a power meter I just bought off of amazon, great pairing.Far more convenient than using a DVM...https://www.amazon.com/gp/product/B07XG7F269/Also, using a variac is the safest way to turn on old equipment ... very slowly, watching input power and to to gently informally reform caps in the old equipment.Most old equipment use a line transformer to create the lower voltages required. So with slowly bringing up the AC line, very slowly, and leaving it there for a bit, watching input power, slowly impresses a lower voltage across the old capacitors, and can safe them.Newer equipment use a switch mode power supply, and it's off till you reach it's AC low line operating input voltage, than it snaps on.. and the low voltage outputs are at or near their specified voltages. So no way to slowly bring up equipment with a SMPS as the front end.And for safely "firing" up new designs running from 120Vac. Which is most of my use.Arrived with zero damage, ready to rock.

Used to test a diy amplifier and it worked well. The small meter was off by a few volts but is just meant as a rough indicator, I marked my target voltage on the dial after checking with a multimeter so no issue. A good value overall.

Works great but always remember that with any autotransformer like this one (any VARIAC) THERE IS NO SEPARATION FROM THE HOT 120VAC LINE LIKE YOU HAVE WITH ANY TRANSFORMER (THE PRIMARY COIL IS TOTAL SEPARATE FROM SECONDARY COIL.IN THIS CASE IN THIS UNIT THERE IS NO SECONDARY COIL.YOU HAVE ONLY THE PRIMARY COIL THAT IS CONNECTED TO 120 VAC AND THE OUTPUT IS STRAIT FROM PRIMARY COIL THUS THE OUTPUT IS CONNECTED ALWAYS INTO THE HOT LINE ADJUSTABLE BY THE ROTOR KNOB ON THE TOP.IT IS A MATTER OF SAFETY.YOU HAVE TO EDUCATE YOURSELF ABOUT USING ANY AUTOTRANSFORMER BEFOR USING THIS ONE!!!

This was off my a bit. Used a multimeter and sharpie to annotate where the voltages I needed were. Seems ok.

This is a serious tool I used for a frivolous reason. This worked great to dim holiday tree lights that I just find to be too bright (all of them). I tried to use a lamp dimmer, but the leds would flicker/blink/strobe if turned very low. This transformer/variac allowed me to vary the voltage infinitely. This seems like an expensive solution, but I had spent more than $20 a string set for lights I hated. This purchase fixed my problem. What I did notice is the different led colors dimmed at different amounts once I got them very very low. For the life of me I can’t remember which colors were the brightest and which dimmed the quickest. Overall I was happy I was able to look at my led lit tree in the dark without wanting to squint. The Variac/voltage variation transformer is shockingly heavy. The feet are rubber. The knob at the top is plastic. It came with extra fuses that I did not need but it’s nice I have them. Now that I know what this does I will use it to adjust fan speeds to where I want and for a soft start on some electronics if I ever need that.

Great for working on old electronic equipment such as vintage radios. Note that this provides zero isolation, so use along with an isolator for safety.

Used this to generate test voltages. It did fine.This is an engineering tool, not really a consumer product.One needs to consider the application before using it.Read the "bad" reviews and the users do not seem to understand the equipment. This device provides a voltage, but is not regulated based on load (has high internal resistance). The meter is there for a general reference. For any sort of precision, an external voltage meter is necessary. The full load current is probably not valid for entire range. Test unit in use case before putting into service.