EBC-A10H BatteryTesting Machine Mosfet Failure when activate dose not turn off

[sam_sam_sam]

Re: EBC-A10H BatteryTesting Machine Mosfet Failure when activate dose not turn off

Well here is an update…..——>

….——>

The controller portion of charging circuit goes to 5.5 amps and is uncontrollable the discharge still works but I not convinced that there is not something wrong this section as well

I going to modify this mosfet board to only monitor the voltage and current from a home made board with only the current shunt and the voltage input for the controller board and use a 12 volt power supply that the controller board needs

I have reversed engineered the circuit board to be able to do this because I really need a voltage/current computer monitoring system and this will work for how I want to do

I was not going to modify it to this extent but when I saw this type of failure I decided to do this modification because I need the battery tester to be reliable and seeing this troubling behavior I have made this decision

I have another battery tester that is giving me the same kind of behavior it just has not gotten that bad yet

I have bought two more new units to replace the ones that are failing

When I finish the modification on the one that has this failure I will post some pictures of the finished this project

[sam_sam_sam]

Re: EBC-A10H BatteryTesting Machine Mosfet Failure when activate dose not turn off

I tested a battery with a BMS protection board and the results are what I expected them to be one twin 18650 batteries with a

Settings for testing BMS 4.2 volt board

Battery tester 4.2 volts @ one amp
External power supply set at 5.0 volts unlimited amperage to 3 amps

The results of charging curve was what I expected it to be with a slop to zero amps and the voltage stayed at 4.2 volts when the battery tester finished it runtime the voltage only drop slightly which is what you want

[sam_sam_sam]

Re: EBC-A10H BatteryTesting Machine Mosfet Failure when activate dose not turn off

Well I found out that you have to have the voltage at least one volt above the battery voltage when you select one amp on the battery tester for it work correctly this is very informative to have to operate this battery testing machine to test battery BMS protection boards to keep it from spiking voltage on the mosfet in the battery testing machine control board was not designed from the factory to do this correctly I had to modify the mosfets board and use a separate XL4015 buck converter to set the voltage for the battery that you are testing

I can not completely sure if the XL4015 buck converter on the board is setup to turn on/off the buck converter by the controller chip but I have a feeling that it is done this way plus the controller relay for add protection that fine if you are only testing battery by them self with no charging controller of any kind but this does not work well if you are using BMS protection boards or charging controllers for battery bank power supply this becomes the problem

[sam_sam_sam]

Re: EBC-A10H BatteryTesting Machine Mosfet Failure when activate dose not turn off

This battery testing machine has become more versatile than I had expected it to be but not with out modification to the mosfets/controller power supply circuit board and without adding more inputs to the device that are not there now

I exporting weather or not I can modify the buck converter circuit because I have some of the same exact buck converter ic chip boards that I bought from EBay I just need for them to be shipped to me so I can see how I can modify the circuit boards on the battery tester so I can adjust the voltage going to the mosfet circuit

[sam_sam_sam]

Re: EBC-A10H BatteryTesting Machine Mosfet Failure when activate dose not turn off

Okay I have answered the most important question that I had about weather or not the battery tester would work on 5.45 volts with out give me any problems charging one 18650 battery cell set at one amp and voltage set to 4.20 volts

So I can check BMS protection boards with out voltage spiking the mosfets which is the most important thing because I can now do this more safely than 24 volts on board power supply

Now I have to figure out how I going to set it up to battery bank charging monitoring which means that I do not need the mosfets for this setup I just need the current shunt portion of the battery testing machine in this mode

I put the new mosfets in and I have a miner problem it shows on the volt meter a small voltage on the meter 0.01 volt to 0.30 which was not there before which could be that I have not cleaned off the flux off the mosfets/controller power supply board

More to come later and some more pictures also

[sam_sam_sam]

Re: EBC-A10H BatteryTesting Machine Mosfet Failure when activate dose not turn off

Well I have answered the question I was asking if it could be done correctly and the answer is yes it can with a twist I will have to put a 24 volt relay to make sure that it is not activating the two power supply at the same time by accident but I all have to do is put the negative side of the power supply to where the negative side of switching power supply that is part of the battery testing machine and the positive side of the power supply goes through the mosfets and so does the battery positive voltage as well this is the reason I will have to use a relay to isolate the two different power supply

So now I have to decide on how I am going to hook up the external switching power with the connection to the current detection board to the outside world and how I am going to switch the relay either it will be in the front of the enclosure or in the back of the enclosure

So this modification is going to be easier to do than I thought it would be but I have to make some decisions on how I want this to work
Or I could remove the relay that is in there now and use a different type of relay that has more terminals on it which might be easier to do in the long run

[sam_sam_sam]

Re: EBC-A10H BatteryTesting Machine Mosfet Failure when activate dose not turn off

Here is the data sheet for the buck converter ic chip
https://cdn.badcaps-static.com/pdfs/...99e3c5b9eb.pdf
This device is interesting it can be controlled by a TTL signal and it also shows you what components you need to make it work in figure number 9 at the bottom of the data sheet

As you can see in the picture I have found the current sensor wires one of them is the common negative side of the battery side and the other side is the power supply side of the controller so this might be very easily done but I can not just power the board with a 5 volt power supply because this board also has a 12 voltage regulator that is the device that is on the heat sink but it is what I was hoping for and that the power supply side I was able to find the current shunt wire which I did now I have to find out what the resistance of the shunt device is so I can closely match it as possible and then I can do what I want with this battery testing machine

[sam_sam_sam]

Re: EBC-A10H BatteryTesting Machine Mosfet Failure when activate dose not turn off

Now it is time to reverse engineer this battery tester machine current sensor portion of this circuit to be able to use on my usb charger and we will see how this goes if it can be done and work correctly or not stay tune for more to come sense this battery testing machine has had this malfunction I do not have much to loose if it goes horribly wrong and I end up with a useless device it kind-a already this way now anyway because the only part that works correctly is the volt meter section and it does connect to the computer and still plots the voltage right now so is kind-a useful but I going to gamble on the odds that I hope to succeed in this project and hope for the best

But first I will put the the new mosfets in it and see if I can bring it back to life and go from there
I have to remove the mosfets and the current shunt and try to trace where the two wires that measure the voltage drop and reroute these wires and put the current shunt on a separate circuit board and see if it can be used this way or not if it can then I will put a selector switch so I can go back to the original way that it is suppose to work or at least this is the plan of action I am going for

If I can get this to work correctly I will post some pictures of this modifications that were made and how you go about doing this modifications if anyone else would like to have this option for there battery testing machine

Because I have already decided that if it goes horribly wrong and I have to buy a new one to replace it so be it

[sam_sam_sam]

Re: EBC-A10H BatteryTesting Machine Mosfet Failure when activate dose not turn off

Can someone please explain to me what the difference between these two part numbers

IRFP250M

( this is part number that is in there now )
bought 8 of them from Newark.com that all they had in stock

https://cdn.badcaps-static.com/pdfs/...784f7a8ca8.pdf

IRFP250N

bought 10 of them from Newark.com they have plenty of them

https://cdn.badcaps-static.com/pdfs/...d14dbbddbb.pdf

One website says that it is heat temperature dispassion but I took a brief look at both data sheet and could not see any real difference between the two of them unless I am missing something but I ordered both of them

[sam_sam_sam]

I have an issue with this battery testing machine that if you activate it for 50 milliamperes charging mode it does not do this correctly it goes to 350 milliamperes and does not turn off until I power cycle it then it will be in the off state

If I remember correctly it is a IFRP250N
The Mouser part number is IRFP250PbF lead free version is the only type that is available now
I can seem to find them at Mouser it seem Digikey shows them out of stock lead time 66 weeks lead time

I going to order some but senses I have to repair this because of this failure I going to see if I can modify the charging controller to charge from my 5 volt 5 amp power supply so I can use my usb charger setup to test usb battery packs because the usb battery tester that uses the same exact software has an issue where after a certain amount of time it shuts down and stops counting the the amp hours correctly

I will post some pictures of this repair when I receive the parts from Mouser because I have to order some other parts from them as well for another project

When I order some of these mosfet I going to order enough of to have spares to repair the other two battery testers that I also have