New project with NUBM37 125W

[Borislav@87]

The problem is in the driver at 100%. He couldn't handle NUBM35 before, what's left for NUBM37. On the NUBM35 it couldn't get more than 3.6A at 4A set with the same battery pack and the 20V/50A drill battery (charged to 100%) Battery terminals are not cold. It works perfectly. The driver just doesn't work. Try with a few batteries and you will see. Make a 16V or 20V pack and connect and see.

 

[RedCowboy]

I turned the unit on my NUBM38 up to 4.5A and it runs it no problem, I am using 8 cells ( 32V ) supply.

Hold on and I will test with only 6 cells.

 

[Borislav@87]

Even a 12V/100A car battery couldn't handle it. Apparently it is impossible for this driver to work well with low input voltage. If I put 50V into it it will probably handle it but the goal is to handle small voltage like 12,16,20 and 24V.

 

[RedCowboy]

Ok I just tested with my NUBM38 @ 4A with only 6 cells ( 24V ) and no problems, ignore my camera clicking it's old and messed up.

 

[RedCowboy]

Now if I put my old panasonic NCR 18650 cells in ( 6 for 24V ) then it would not work, because they can't carry the load.

You should at least fully charge your 18 cell 24V pack and try it.

 

[Borislav@87]

If you don't have a problem, mine are probably a bad batch. Both numbers work equally poorly. You reach the set values very quickly. It happens very slowly for me. Both my drivers have the same results. If they can't handle NUBM35, they're clearly a bad batch.

 

[Borislav@87]

Tomorrow I will charge the 24V battery to 100% and test again what the result will be

 

[RedCowboy]

That would be interesting to see, because it sagged hard to do 2A in your 1st video, but starting at 20.8V your 18 cell ( 6 cells of 3 ) would only be 3.47V per battery so yea, it needs to be fully charged and flaoting around 4.1 - 4.2V each or 25v for the pack.

 

[Borislav@87]

Let's say it wasn't charged, but why couldn't it handle the NUBM35, like, it also didn't handle the drill battery. It is strong enough to power the NUBM35. Strangely, the result was the same with both batteries, and the drill had 100% charge.

 

[RedCowboy]

Your batteries sagged from 20.8 to 16.1 and that shows your batteries are struggling, I just tested 8 cells driving my nubm38 @ 4A and they sagged from 32v to 29v that's 3.62V each cell, so your cells sagged to 2.68V ....no wonder the driver couldn't output any higher, it is your battery. Try charging your 18 cell pack and forget that 20V drill battery, it's just not up to the task no matter how long you charge it, it's a cheap drill and the pack holds 5 x cheap 18650's.

You do want full output from your laser array.... Right ? You need to feed it.

 

[Borislav@87]

I'll check in the morning. The battery of the drill is 5 pieces 21700

 

[RedCowboy]

How much did you pay for that drill ?

 

[Borislav@87]

35 euro

 

[RedCowboy]

I tested my 20V lithium battery pack 4Ah that has 10 x 18650 is series/parallel 5 pairs of 2.
I didn't run it long because my fan wasn't running without my normal batteries.
Your parkside is also 4Ah so it should drive your nubm35/38 @ 4A when it's fully charged, but for how long I don't know.

 

[Borislav@87]

I can't tell by how much, but I don't feel a drop in laser power with more work. After the battery goes down, its power suddenly drops. It has Bluetooth which shows many things on the app like current, amperage consumption, charge cycles, battery level, discharge setting and more

 

[RedCowboy]

I didn't think your drill battery would be all that good, but 5 x 21700 is not bad, still it's not going to run continuous for very long, but it should work for a minute anyway. Maybe you got two bad boost boards, but let me know how your 18 cell pack ( 6 X 3 ) works out fully charged.