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Atorch DT24P: High current cell/load capacity tester - Has anyone got or used one of these?

gyrex

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Note: This thread is about the DT24P not the DL24P (with the large fan)

I'm about to start building my second hybrid solar system (sold my home and building a new one) and one of the things which I wish I did on my previous build was to test the 280Ah LiFePO4 cells prior to putting them into production but I couldn't find a reasonable capacity tester with enough current at the time.

In my research for the next build I found an interesting bench tool which could provide the solution and was wondering if anyone has one of these or has tested it? It's a DT24P (https://www.aliexpress.com/item/400...o.store_pc_groupList.8148356.6.ae3de622iuiVmJ) from Atorch and it uses a shunt and external loads to measure and report capacity of the supply. If I put 2x 100W 0.15Ω resistors in parallel, I should be able to draw around 40-50A which would mean I could test a 280Ah cell in around 6 hours at 0.2C for around $30AUD (including resistors & relay) - not bad if it works well! It also has the ability to wire up a relay to disconnect the load when the voltage reaches a configurable low voltage mark. It certainly ticks a lot of boxes and at this price, I could buy a few of these to test many cells concurrently...

So.... has anyone on here tested one of these puppies?
 
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I just received a DL24P from the ATORCH AliExpress store and it is dead on arrival. It won’t power up. Sent them a message a day ago and have heard nothing back. That’s the problem with AliExpress is no way of affordably returning broken items and doesn’t appear ATORCH cares. We’ll see. I’ll report back if they correct the problem.
 
I just received a DL24P from the ATORCH AliExpress store and it is dead on arrival. It won’t power up. Sent them a message a day ago and have heard nothing back. That’s the problem with AliExpress is no way of affordably returning broken items and doesn’t appear ATORCH cares. We’ll see. I’ll report back if they correct the problem.
I've got a DL24 already (works fine) but I was after a tester which can pull more load from the source which is why I was interested in the DT24P. Anyway, I hope you can resolve your issue.
 
I have had good luck using an ET5410 or a KP184. Both are around $200, and can test a cell at 40 amps, or a 12v pack at 28 amps. The ET5410 is much easier to use, but the KP184 has sense leads (more accurate voltage measurement). Like any electronic load, you can parallel them for higher current tests. For higher current pack tests, just get a shunt and use your inverter. The link you gave is just a shunt, use an inverter instead of a resistor.

To quickly test individual cells, the Zketech ebc-a40l is the best. Shop around, I managed to buy one for $176 including shipping, but it is mostly over $200 now.
 
I just received a DL24P from the ATORCH AliExpress store and it is dead on arrival. It won’t power up. Sent them a message a day ago and have heard nothing back. That’s the problem with AliExpress is no way of affordably returning broken items and doesn’t appear ATORCH cares. We’ll see. I’ll report back if they correct the problem.
I made a quick video explaining how to get everything working. I wasted about 15 minutes thinking it was dead on arrival because of the fact that it has two 2.1mm DC input jacks, whoever did that should be fired. Try plugging your power supply into the one on the back, behind the fan, and see if it works.
 
Apparently, Kunkin has heard complaints about their interface. They have a new model with a color screen, so it should be much easier to set up and operate manually now. I haven't tried one, but it looks promising. You can check EEVBLOG, there is a nice bit of software there that will do data logging for most instruments, and the KP184 and ET5410 are both supported.


Software (and yes, supports the DL24P):

 
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one of the things which I wish I did on my previous build was to test the 280Ah LiFePO4 cells prior to putting them into production

What were the issues you encountered with your previous system that you are hoping to avoid by capacity testing each cell?
 
Mine works fine. Very accurate. Use the rear power input, make sure power supply is rated for minimum 1 amp or more at 12VDC, otherwise your load amps will be limited. 20 amps is max on a 3.2V cell, not 10. Use 10 ga wire, keep as short as possible. No alligator clips. Use high quality 1/4” 10ga ring terminals. Very accurate. I’ve found a lot of junk grade B cells from AliExpress. Now I buy from two on Alibaba. Good luck.

I also use a ZKETECH, 40A. Nice, very accurate too.
 
I made a quick video explaining how to get everything working. I wasted about 15 minutes thinking it was dead on arrival because of the fact that it has two 2.1mm DC input jacks, whoever did that should be fired. Try plugging your power supply into the one on the back, behind the fan, and see if it works.
Yes I saw your video and made sure I plugged it in the correct port. So far ATorch has been pretty slow to answer messages and is trying to just give me $5 back. Hopefully they will give a full refund or send a new one.
 
I have had good luck using an ET5410 or a KP184. Both are around $200, and can test a cell at 40 amps, or a 12v pack at 28 amps. The ET5410 is much easier to use, but the KP184 has sense leads (more accurate voltage measurement). Like any electronic load, you can parallel them for higher current tests. For higher current pack tests, just get a shunt and use your inverter. The link you gave is just a shunt, use an inverter instead of a resistor.

To quickly test individual cells, the Zketech ebc-a40l is the best. Shop around, I managed to buy one for $176 including shipping, but it is mostly over $200 now.
I agree that an inverter/shunt would be ideal but I won't be able to test single cells using an inverter (my Victron MultiPlus II 48/5000VA has a minimum DC input of 38V) hence the need for a device such as the DT24P which can test single cells at lower voltages but still draw a high current load.
 
I'm actually referring to the DT24P, not the DL24P. Uses a shunt and supports up to 100A loads (use a power resistor bank) and relays to shut off the load at a programmable low voltage mark.

View attachment 67959

Link to Aliexpress seller: https://www.aliexpress.com/item/4001159364475.html?spm=a2g0o.productlist.0.0.19443ca2EYAiwn&algo_pvid=42d47263-8bdd-4beb-a674-ff44c99758bf&algo_exp_id=42d47263-8bdd-4beb-a674-ff44c99758bf-0&pdp_ext_f={"sku_id":"10000015023160441"}
Atorch seems to make reasonably accurate load meters. The relay connection looks really close to the current connection, be careful it doesn't short out. Their etest software sucks, and a relay capable of 100 amps reliably will cost extra, as will whatever you decide to use as a load. I have not used that model, but I suspect it will work reasonably well.
 
What were the issues you encountered with your previous system that you are hoping to avoid by capacity testing each cell?
I found out after the fact that 2 of my 48 cells had a much higher internal resistance and lower capacity (tested at ~260Ah vs the others being ~280Ah). Had I picked this up soon after receiving the cells I could have raised a dispute with the vendor and/or credit card company.
 
Atorch seems to make reasonably accurate load meters. The relay connection looks really close to the current connection, be careful it doesn't short out. Their etest software sucks, and a relay capable of 100 amps reliably will cost extra, as will whatever you decide to use as a load. I have not used that model, but I suspect it will work reasonably well.
I've bought a bunch of 0.2Ω 100W power resistors from Aliexpress for around $2 each. 3 in parallel will draw a total of 48A (50W at each resistor) at 3.2V nominal which will suit my testing purposes. I'll buy a few of these capacity testers so I can test a few cells concurrently.
 
I found out after the fact that 2 of my 48 cells had a much higher internal resistance and lower capacity (tested at ~260Ah vs the others being ~280Ah). Had I picked this up soon after receiving the cells I could have raised a dispute with the vendor and/or credit card company.

Fair enough, it is faster to assemble and use the pack rather than capacity test each cell. I would spend money on a BMS that reports on IR rather than a tester.
 
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