MakerHawk Battery Load Tester - 180W 200V 20A USB Load Tester 4-Wire System Adjustable Constant Current Voltage Discharge Lithium Battery Capacity Tester Electronic Load Tester

I've only used it a few days, but it works great compared to the 4 resistor purple board version. That one lost the capacity when turned off and back on. This one remembers settings, capacities, also has several modes to discharge batteries. The early version had 2 dials and you had to adjust it often to pull 150 ish watts. This one has a constant power setting. Set it at 145 or so and it will pull that no matter what the voltage as the batteries drop. Wiring on the purple board units is a little strange. Look at the diagrams. All 4 terminals have to be attached. I do like the full color hi-res display. The 4 resistor purple board "said" color display. But it is definitely monochrome. It was returned if you can't tell. The full color unit actually had some instructions, which were a little criptic... But it was relatively easy to figure out. I do like the on off switch they added as well...

If you are repairing battery packs, this is a must have

First off, this is an excellent battery load tester, if perhaps not for the faint of heart, but then perhaps the sort of person who's likely to want to do this sort of device testing will be used to this sort of rough-and-ready experience. This model is the more featureful one, and given that even as a novice I ended up using a bunch of the features not otherwise provided in the cheaper models, I would suggest that you get this one, rather than one of the slightly cheaper ones. This product seems to be excellent value for money, and I think that getting a cheaper one would be a false economy, especially if you factor in your own time. The product itself is well constructed, but not exactly what you would call sturdy, since it's just a circuit board with a bunch of components soldered on, and standing on four standoffs for legs. If you drop it, it may well be toast, so be careful. In my case, so far I've been using it to measure the capacity of cordless tool batteries, and the output of USB power supplies, both of which tasks it's performed with aplomb, though I had to futz around a fair bit, doubtless because of stupidity on my part, but also because of the issues outlined below. When testing 20V batteries, I had no trouble running them at 7A, so 140W, and the device had no trouble keeping cool (see thermal images). The attached graph shows the Win app's display after one such run. The battery topped out at 2.8Ah (it claimed to be 7Ah). It's worth noting that the save results button, which is just below the "Is:" display on the top left gives an option to save the graph, but it doesn't end up saving all of the results above the graph, which is silly. Screen shots are a better idea. From the same menu, you can also save out a CSV with second-by-second data. As I said, I think that this is a great product at a great price. Still, I would have preferred to have had the opportunity to pay a little more to get a better product. Here are the problems I had: * One important thing to understand about this product is that it has experienced a modicum of badge engineering. As far as I can tell, the manufacturer is really "aTorch", so searching for "MakerHawk" has limited utility. * My version came without any documentation whatsoever. I don't know if this is a systemic problem or just a packaging issue in my case. I was stuck googling around, but mostly came across (really terrible) docs for the older/cheaper models with knobs. I eventually found the manual. I can't give the URL here, but if you google you ought to be able to find it with this search term: site:device.report "atorch bw150 user manual pdf" * I found that I had no trouble getting the device to connect to an Samsung Galaxy Tab A (SM T580) Android tablet using the "SmartLife" app, which I happened already to have installed. Having said this, it's pretty clear that the Bluetooth connection/control method is less desirable than the real Windows app. The app can be got from the URL in Section 6 "Online Instructions" of the above-mentioned user manual PDF. This gets you a zip file with a directly executable Windows application (no installing required), and definitely works for me under Win 11. * The device comes with no power supply. This is (kinda) documented in the manual, but it would have been nice to know that before getting it. You can power it from a USB port in the middle on the back, or from a DC12V power source also connected at the back on the left. I happened to have a spare DV12V power wall wart supply, so I ended up using that. The device does come with a USB-A -> USB-C cable, which you could use to power it, but you'll need that to connect to your PC so as to get a direct connection to the app mentioned above. This latter connector is mounted on the right-hand side near the front of the device. * You're kinda on your own to figure out how to use the device, though you may find a tutorial video or two, if you're lucky. I found that the display on the app was definitely the best way to see what's going on, but editing the parameters in the app never seemed to take effect. I suspect that having the Bluetooth/Android connection running at the same time was getting in the way. I did find that there's no visible means to reset all the counters using the Windows app. I hunted pretty hard, but failed to find anything. I did, however find it possible at least some of the time to reset the counters using the Bluetooth/Android method. Not sure what's going on there. I ended up figuring out how to change parameters by using the four buttons on the tester device itself. This was a really weird UI experience, and nothing like any suggestions I saw on YouTube. I kept hearing that doing multiple clicks and long clicks would work, but that definitely did not work. I eventually found that clicking the top button seemed to move a little underbar cursor along the parameter value to be changed, and the left/right (+/-) buttons would change the value for that specific digit. That is, each digit had to be selected with the underbar, and then edited individually. This isn't a huge burden. It just took a while to figure it out. So, the bottom line is that this device definitely worked for me, and was definitely worth it. Above and beyond the mysteries of the documentation and UI I discussed above, there are two other things which I wish I had a chance to throw a little more money at: * I wish that there was an option to get it in a box. This would definitely have been worth another ten bucks to me. Yes, I could get a box myself, but installing it would actually be very hard, since all of the connectors, controls and the screen are directly mounted on the PCB. It would be tough to move all of these, or remotify them in some way. It would be a simple matter to make these indirectly wired to the PCB at manufacture time, in which case getting it into a box would be simple. * The first task I wanted to tackle was to test cordless tool batteries. These batteries are carefully designed to make it hard to reach the contacts accidentally, making it hard to short out a battery in your toolbox. There's no way that I could get the clips for the two leads provided to connect to the test samples I had. If the product came with another upsell of a pack of test probes of different types, I would have snapped it up. Again, yes, I can make my own test probes and get them to fit, but the cost of my time to do so is wildly greater than what they would have charged for a diverse pack of probes. I couldn't wait, so for my task, I ended up jamming paperclips into the battery terminals, and connecting to those. Kinda terrifying, but it got the job done.

Plug in the 12v power supply to the back. Prepare your phone for the QR code to download the app if you want to monitor the settings remotely (you can operate the buttons from the app). I had to pair with specifically one of the two new bluetooth broadcasts. I believe one is for android, the other for iphone. The app will show some insane 600v measurement graph-- you can zoom in with finger gestures to get down to the typical 12V range. To test battery capacity: Screw down the fork leads to the front left green connector block. The black fork is closer to you- red closer to fan. Make sure you open the connector block first with flathead screwdriver otherwise you'll likely screw down the forks in reverse by a counterclockwise motion and the forks (or USB board) will dip up at an angle. Attach leads to battery (or cell). Set the cutoff voltage to your particular battery (or cell). You need to know this!!! For a 12V Lifepo4 battery capacity test above 15aH battery: make sure it is fully charged. set cutoff to 10.5V. clear data (this just clears the test metrics and gives clean slate). You'll want to use CC to test capacity. Set CC to max allowable: you will probably start at 13A and work up to the 14A range (if you're in no rush, set it lower). Keep note of the MOS temp range and don't exceed 99C. Don't even up that in the settings. You can get 14.3A+ if you prop up the tester and have a fan blowing under the heatsink and the mainboard. Try not to exceed 180W. This advice is for 75F ambient. Be more conservative with the amp settings if ambient is hotter, you'll burn up the MOSFET under the heatsink. If you trip the temp alarm too much it will stop the test. You can resume, but you need to lower the amp draw first or fix your cooling. Don't push it! You can test a 314Ah 12V battery in under 24hr with the above method.

Right out of the box, it looks great and has a pretty good looking display. I plugged it in and used my e-bike charger to test it, it worked fine for the first 15 or 20 minutes running at about 130 w. My ebike charger is rated at 67V and 2.5A, so I started pushing up the power .1A at a time. when I went from 2.3A to 2.4A (around 140 to 150 'ish watts) I tripped the overpower protection, which should have been fine all the way up to 185W. After I unplugged my charger to clear OPP, I want to reattach it to see if that was some weird issue or if this is truly cheap garbage. When I attempted to reconnect the alligator clips to the wires on the charger, it combusted into a blinding flash. I can only assume, whatever flaw tripped OPP must have caused a permanent Short circuit effectively killing this admittedly nice looking but ultimately useless piece of garbage.

UPDATE - I am upping my review to 3 stars, and I am hoping for 4 before the end of the day. I got it to work after a few hours of experimenting. And although I am missing the hardware on the output monitor connections, I did find that the mounting holes are spaced 7.5mm and will fit any number of connectors. Unfortunately, the lack of clearance from the cooling fan and heat sink limit my options, but if I install this in a case and break the connections out, that's not a problem. Just route that out to a couple of banana plugs. Same for the 4 port inputs. I am still having a heck of a time finding software. Nothing I have tried has worked, with Windows 11 that is, and I am about to go after Linux with a Python environment. Using Nirsoft tools, I found the device when I plug it in. It's a HID device and no COM ports are added when plugged in. Bluetooth still looks to be non-existent. The board looks to be a solid build, and my tests placing a load on a power supply have been very useful. But I need to log my results over a number of load samples so getting it to work with my PC is important. If I can solve that, check calibration, and push it to the limits and have success, I'll up to maybe 4 or 5 stars, and I will come back to do that. PREVIOUSLY..... I am giving this 2 stars instead of one because it actually turns on, and I can navigate some menus. That is it though. There are so many differences with what I received and what is shown on this web page. For one, on what I got, there is no output jack (as shown in the images). There is also a few other missing components. I do not see a BlueTooth board, although there is a built in antennae. I never found a way to turn it on nor did I see the icon on the screen. There is also some module that goes in a slot, according to images, but it is empty on what I got. The screen menus and layouts are different than what is shown here. I have tried two manuals so far that say ATORCH DL24P and neither describes the menu button presses accurately. And is there a schematic anywhere? Where is the board version number? I realize this is Chinese and you live with the lack of documentation, but I am concerned I was short-changed on features, or worse, something critical with this board. On the fence about returning still.

I started making my own battery packs & rebuilding them too. This works well and connects to my phone for display… was a bit of learning to use it, but now I’m very happy with it! Great for smaller batteries! Will do bigger batteries just would take a while for results.

I have MakeHawks other load tester and it has been working good, however it doesn't have low voltage cutoff like this one does. This tester allows you to set the low voltage cutoff so it can be used with lead acid and other batteries that do not have a built in BMS. This tester also has separate leads for the amp draw and the voltage reading. This should make this unit more accurate, in fact the voltage reading at the tester was very close to the reading I took at the battery with my Fluke meter even under load. I have seen some reviews saying this unit wasn't accurate so I will be doing some more testing and will update if I find this to be true. The cooler on this unit is also nicer being that it has plastic around the edge, as the cooling fins on the older unit is very easy to bend. The plastic, which also looks neat with the LED's helps protect the cooling fins.