DROK 20A AC to DC Buck Converter

I am using this Drok 115VAC to 24V 20A variable power supply, along with a YaeTek 24V DC 350W Permanent Magnet Electric Motor, to drive my Taig Micro II lathe. Considering this whole kit cost about $80 I'm very happy with the result. While not perfect, the value is so high I have to give it 5 stars. If you've been thinking about one of these motors for your micro lathe I say, go ahead! If you are running the 115VAC Marathon motor that Taig sells, then you know about that motor. It's OK, but the speed range with the 4 step pullies is 430 RPM to 1725 RPM, pretty high for larger parts. And it's big, heavy, and kind of brutish - there is no way you need that much power, nor can it even be transmitted with the stock belt. This DC motor setup runs well down to about 5 volts/570 RPM, which is a lathe speed of 140 RPM. It will go a lot slower, but it sounds a bit notchy. It's happier above 5 volts, and I usually have it set about 16 Volts, which makes a lathe speed of 450 RPM to 1800 RPM. The power supply goes to 28 volts and the motor is spinning at 3200 RPM. This PS has been flawless in this application. It is the voltage regulated only model. Using a "Kilowatt" meter I'm seeing up to about 120 watts in my application. So, about 5A at 24V. The PS seems perfectly happy, and the fan has never turned on. Judging from the motor whine while running the lathe there is a very minor variation in RPM with no load, just a few RPM or small fraction of a percent speed. Under cutting load I've not noticed any significant speed change - it does sound like the system is working harder but that's normal. The motor has plenty of torque for this application. At 7V I have no trouble machining 2" diameter aluminum at a no drama SFM. Once again, the belt is the limitation. The only negative for me is the motor is kind of loud. It makes an ever rising pitch and volume whine as RPM increases. I only use this lathe for occasional small parts, so the noise doesn't matter. If you are doing production, it might get tiresome. Who knows how long it will last. Considering it's intended use as a scooter motor I'm hoping with this very light lathe duty it will last forever.

I got this to kind of use as a benchtop supply. I had a variety of DC motors I needed to test, at a variety of voltages and power ratings. They were intended for battery powered applications, but I didn't have the variety of batteries I would have needed to test them. I looked at actual benchtop power supplies, and they all seemed to top out at about 10 or 11 amps, and were much more expensive. Before ordering this, I hadn't seen anything like this before, although they look to be pretty common. I also bought some leads that I connected to it to make it easy to connect and disconnect what I am powering. It worked perfectly. Provided the voltage range and current I needed and one of the motors, was 24V DC and drew 17.5 Amps, which this provided with no complaints. While I do appreciate the Voltage indicator as a rough guestimate of the voltage, probably "good enough", I did hook up a more accurate meter to set the voltage during my testing. It was easy to get it to within a few 10ths of a volt, but getting it much finer than that took a very delicate touch, but with patience, I could even get it to the hundredths and once there, it would hold it. I see they have another model where it has both voltage and current limit adjustments, and I am thinking I might pick one of those up too.

24V 20A with Dual Gauges. Ordering these cussed things is a problem, there are so many versions that are almost alike, triple check the details. Drok is good stuff, so while there are many other brands, put them at the top of your list. I wanted a ‘booster’ battery charger for 12v lead acid and agm batteries, as I store about 50 every winter and have issues with lifespan. I already own 3xRediPulse Pro-12 maintainers that put out 0.75A split between 12 batteries. They need to start with mostly charged batteries. Charging one battery at a time is a hassle. Jumper cables are a hassle. So I bought this supply, knowing it was ‘stupid’ and hooked it up in parallel with my smart 10A charger (6.5A real) on up to 16 batteries at a time. On arrival I was disappointed because I thought I was buying a 50A one, and the instructions (junk) said it will only supply 10A, which I had no interest in. But I also got the rest of my kit for my system so I pushed ahead. Note the dual gauges, red for voltage and blue for current. That is SWEET! And the paperwork supplied that said 10a is gibberish, this baby puts out 20A all day. With all my wires hooked up (And yes Virginia, this is nutballs dangerous without fuses, note the damaged junction boxes.) and plugged in, I turn up the voltage and watch the amperage go up. Think of electricity as water. Voltage is pressure, Amperage is flow. Now modern battery chargers are wicked smart, and do lots of things super well. But my 10A smart charger only puts out 6.5A. I know this because I have a DC clamp amp meter. I want speed, but no damage. By setting the voltage on this charger at 13.3V, when the batteries are discharged I can see 20A. As they charge the amperage goes down. If the batteries are only accepting a trickle charge (as seen in images) then I can turn up the voltage (left knob) and push more juice in, but I’m boiling off water. If you use this to charge batteries, don’t turn up the voltage knob to where it shows 20A. Stop at 19.9. Otherwise, you don’t know if the knob is set for what the gauge shows, or much higher. For instance, when I first plug this in, it might only show 13.0V at 20.0A. If I cranked the voltage knob up, it would still only show 13.0V and 20.0A. But when I walked away, the batteries would fill, and the voltage would climb and climb to where the knob was set. So I only charge at 20.0A while watching (The cool dual gauges!). When I walk away, I like to see less than 18A, just in case. So my smart charger pushes out 6.5A and this baby starts at 19.9A and drops as the batteries charge. If you are charging one battery at a time, even an 8D, get a smart charger. This thing will kill batteries in a heartbeat if you don’t understand the process. Excess voltage boils the water, and this thing will cook forever at 20A. I assume it will do 24V no problem, I could test it with two batteries in series, but—I’ve seen enough sparks. The dual gauges are the bomb. I have so much comfort knowing what is going on. Being able to ‘goode’ the voltage and watch the Amos go up tells me quite a bit about the state of charge. The second knob is for limiting the current to a lower amperage. I turned it down a bit because it will charge a bit above 20A and might burn itself out. That knob is of no value to me, but certainly works. Do not install in a vehicle. The knobs are precise but with almost no resistance. I fear them moving. The fan runs continuously at higher charge rates and every 10minutes for a minute at 7A. At 20A the case is slightly warm. This deserves five stars, but if you’re a smart consumer, read the lower ratings. Drok was close, but I don’t like the loose knobs, no power cord, and since it has knobs it should be more end-user rather than looking like a built in power supply. The wires going in are getting abused. It has a 50A ATO fuse below the current knob. Why 50A? It has a silly tiny switch that might be an on-off switch under the voltage knob. O/O would be nice. The current goes to zero but it still reads the voltage. Better instructions would be nice. If you live in the USA, FLIP THE HIDDEN SWITCH to 110V. They are shipped set on 240V. Good luck. I bought the 24V one because I wanted to charge batteries, not just have

all good thanks

Great item nicely packaged

Bueno

Stable output voltage

Used inverter to replace the battery setup for my water faucet. (Touch on/touch off). Adjustable DC voltage perfect to fine tune voltage at the faucet(9V at faucet supply set at 9.75). Time will tell if the inverter will last. All in all satisfactory for my use.