4000W High Power SCR Electronic Volt Regulator Speed Controller Motor AC 220V 110V

This unit works very well form my application. Easy to install easy to wire. I wired to bridge rectifier to control DC voltage and it worked great

This is rated at 120-240v, the adjustment POT is designed fro 240v so you get very little linearity at 120v. If you replaced it with a 470k pot it would probably work better at 120v. I can't speak to longevity, but it was the better built version of these line of SCR controllers. I couldn't find the ST datasheet for the SCR, so I wonder if it's some special or a counterfeit. Anyway, it appears to be made with the requisite power handling components, but you'll want to put a screw on the heatsink, the manufacturer didn't retain the heatsink to the chassis. Heat dissipation might be an issue at the full rating. The device is wired in-line with your load, it's only necessary to break the 'line' wire to the load, the 'neutral' is just passed through the board. The outer terminals are the line in and out.

I bought this for a project I was working on. The craftsmanship was definitely bottom shelf, but it appeared safe enough. I got it on the bench, applied power, and it popped the moment I did so. I cracked it open, and it wasn't even worth fixing. I did check some components, and found several to be at the edge of their spec. The rheostat was also effectively non-functional when I put a meter on it. The only parts I found any use for were the case and heat sink.

I am using this unit in a shop-built feed control addition to a manual milling machine. It woks as Ihadhoped it would.

item as described i have installed it on my sea saw table and it works perfectly

Used with heater which draws about 800W for hours.

I have one one a recent belt grinder build and it is working so far without an issue. My only real complaint is that the fuses are soldered in, which makes them hard to replace if you were to blow one.

good

Item arrived on time, which was good. The picture on Amazon shows the terminals labelled in English, but the actual regulator had a Chinese label which threw me for a moment, but in all other respects looked identical. I wired it into an extension lead (careful not to cut the earth wire - just the live and neutral) and then tested the unit with a table lamp: worked perfectly as a dimmer switch for the light. Next, put it on a 2KW water heater that only had an on/off switch. Again, works as expected: I can now keep the boiler on a simmer once it is up to temperature. 4 star rather than 5 because of the Chinese label on the actual item rather than English as per the photo. Otherwise, exactly as described.

Used it to control a heat press and it works great.

Good

This power supply works very well and it provides ac with light loads down to 25v ac.