Adjustable Constant Current Electronic Load - 150W USB Electronic Load Battery Capacity Tester USB Resistor Load Multimeter Voltage Current Tester Voltmeter Meter Amperage Reader 0.2-25A 2-200V

I'm in the process of building a 100Ah LiFePO4 battery pack for the 48v Torqeedo outboard motor that I have on my pontoon boat (I live on an e-motor only lake). I first discovered this device being used as a battery capacity tester in one of Will Prowse's YouTube videos. It looked like an affordable / easy option for confirming that the batteries I bought did, in fact, have the advertised 100Ah . . . so I clicked on his link to the Amazon store. When I got here, I saw the newer version available and went for it! Note again: this review is for the "New upgrade" purple version. A few comments:1) The device is working great! I attached a picture of the 6th consecutive cell that I am running through capacity testing. A little smoke rolled off the device when I started discharging the first battery, but stopped within a few seconds. The resistors on the sides of the heat sink get pretty hot when discharging at the 20A I'm using for this cell (0.2C discharge rate), so I expect it was some residual solder flux burning off. In any case, it didn't affect operation in any way that I can see and it hasn't repeated since the first run.2) The separate discharge and voltage measurement terminals are a must! The discharge terminals measure ~0.4 volts less than the voltage measurement ones due to resistance in my leads (likely the fuse - your results may vary), which would significantly affect measurements. It's a must-have feature, in my opinion, and the older version (the one Will used) doesn't have it.3) There is a PC app that you can download from a janky-looking website (accessed via the QR code on the back of the device) so you can monitor / control the device from your PC. I'm not trusting enough to install something like that on my PC so I can't comment on it, but the pictures looked pretty cool!4) No instructions were included with the device. However, the QR code on the back of the device brings up a site (the one referenced above) where you can download them. Unfortunately, there are several downloads there and no indication of which is the correct one (use DL150B). Worse, they are written in VERY poor English and are incomplete! For example, if you want to erase the data from a previous run, you need to press the button and encoder down at the same time until "Data Erase" shows up. Hold them for a moment longer and it factory resets. Neither function is indicated in the instructions. Nor is any information on how to use this kind of device. If you don't know how to use it, don't buy it until you spend some time on YouTube watching people use similar models (I couldn't find any videos with this version). You're likely to hurt yourself or someone you love!!!In summary, great little device if you're tech savvy and one of those people who only resort to instructions as a last resort. You will definitely leverage those "figure it out on my own" skills here! If your using the instructions as your sole method of understanding the device, good luck! Looking at a lot of the bad reviews, I'm guessing a lot of those folks were in this category.I'm on cell #6 now, but will update my review if anything changes before I get through cell #20! Peace!

Tried to save some money by ordering this used load tester, but it was dead on arrival. All the lights and readouts worked fine, but when you try to dial in the load, it will not move beyond 0.01A. Either the board is defective or someone previously damaged the unit. Wrote a note to reseller to see if there is any troubleshooting I can do before return, but I doubt it. I would be perfectly happy with a used working load tester, but I don't think there is any QA testing on these returned units. Still want a working unit, so if I cannot get a used working load tester, I may go ahead and buy a new unit. Will update review as appropriate.UPDATE: Seller responded to my inquiry, but days after the unit had already been returned and refunded. My suggestion, if you ordered a new or used unit, is to thoroughly check out this device when you get it and make sure the load tester actually works. My used unit looked like brand new, but it was either defective or blown from previous user. Amazon required me to send back the defective unit, but I hope they don't try to sell it someone else again. Lost a week or more on this transaction and still don't have a working load tester yet.

This is a great value for the money and is a chinese load tester. This is NOT a lab quality electronic device and has some flaws in design and in materials, however for what it does and it's price point, it's very useful.Pro's:Can load test high current/high capacity devices up to 150W. Can handle up to 185W for short periods but will overheat for longer tests at this load.Is accurate enough for DIY or general purpose testing. I verified the current readings aligned well with a hall effect clamp style meter. However clamp style meters aren't super accurate either. It also aligned well with a battery monitor/current shunt.Can automatically count amp-hours, watt-hours, test time and will shut down once a final (configurable) voltage is reached.Will automatically ramp up fan speed to cool the heatsink and mosfet based on current flow.Capable of dissipating heat for long continuous load tests such as when testing Lithium batteries.Con's:The terminals are small for the heavier load levels and make it hard to connect large enough cables to remove voltage drop. I used 10 AWG cables which worked ok, but there was a small voltage drop.The current and voltage displays cannot be calibrated and any offsets are permanent. My voltage was off by 0.3V.Can run automatically but I would highly recommend monitoring this device constantly and not leaving it unattended.