Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Testing the Testers
#1
A while back I was thinking about how to test how similar the results from our different testers are.

There has been a lot of discussion about how accurate (or not) the testers are and what sort of precision can be expected during testing.

If we want to see if the our testers give the same results as each other, using a cell to test is problematic - cells behave differently during different conditions that exist during different test cycles. 

Using exactly the same cell with the same TP4056 charger, and the same ZB206 will give varying results from one test to the next.
The same variable test results will occur with other chargers/testers as well.

Therefore, to check how similar the results of our capacity testers are, I thought of using something else to simulate the cell.

I tried using a PC power supply and connecting the orange +3.3v wires and black wire to one of my ZB206 testers and started a test.  The tester started testing happily.  When I disconnected the wires, the test completed.

Next to compare 2 of the zb206 testers results, I ran a timed test for 3 minutes on one of the zb206 testers.
This gave a result of 50mah and 0.169wh

I ran a test on a second ZB206 for 3 minutes again and the results were 50mah and 0.170wh

This looks to me like the results between these 2 testers are very close!  I think that the .001wh difference can be put down to test process error (a slight difference in timing of the tests), rather than a difference between the testers.

Has anyone else tried testing that their testers give consistent and comparable results?

By ruling out the variation that a cell would introduce, this test process seems like a good way to test that your testers are all giving consistent results.

What do you think of this testing of the testers?
Reply
#2
You have s couple of threads of it in the forum
The Ultimate DIY Solar and build place
YouTube / Forum system setup / My webpage  Diy Tech & Repairs

Current: 10kW Mpp Hybrid | 4kW PIP4048 | 2x PCM60x | 83kWh LiFePo4 | 10kWh 14s 18650 |  66*260W Poly
Upcoming: 14S 18650~30kWh | Automatic trip breakers, and alot more
Reply
#3
I had an idea to do this previously, but this is the first time In have done this type of testing and documented the process and result
Feel free to delete the thread if you would prefer I update somewhere else.
-
I just did some looking and could not see a better place to post this. What were you thinking of?
Reply
#4
Testing your testers is fine, but to a degree I think you are wasting your time.

For me the purpose of capacity testing to baseline cells before they go into packs and to confirm a cells isn’t complete garbage.

For the above, consistent testing is more important than accurate testing. Your ZB206 is likely consistent enough from tester to tester to accomplish the goal.

If your tester just so happens to be accurate as well, that is just icing on the cake.

I do care about accuracy, but not really at the cell level. My completed pack capacity testing is when I switch to a different balance aware tester and meter the pack for usable. If the balance stayed close from top to bottom, then than also confirms consistency in testing.
Reply


Forum Jump:


Users browsing this thread: 1 Guest(s)