EGO 56VBattery - What is the T-Terminal?

[@gipielle]

Hello, thanks for the video. I have 5Ah battery that keeps blink green and doesn’t work. Seems stuck on maintenance mode, battery cells are all ok and also ntc. Have you ever get same with this problem or have you some ideas of what I can check ? Thanks

[@ThriftyToolShed]

My very First EGO repair video was blinking green constantly. It was a shorted Transistor on that one.

[@gipielle]

@@ThriftyToolShed thanks ! I have searched on KZbin blink green ego but nothing, I will look at your video !

[@ThriftyToolShed]

kzbin.info/www/bejne/e3mTeIZmnrqtsK8si=LQaJ7mFt09rKuVow

[@youtubular007]

I just got a deal on the big Ego backpack blower that came with 2 6ah batts. Do you where I can find max current discharge specs for those batteries? I called Ego and they don't even understand the question. I want to rig up a use for these packs to another motor but not sure if they can safely discharge 40-50 amps continuous.

[@ThriftyToolShed]

It truly depends on which cells are in the 6Ah and the size of the fuse on the main connector board. This is typically a trace fuse until the packs get up to 10Ah and higher. I know that doesn't answer the question either, but to me that's where to start. So for example some of the older 5Ah had Samsung INR18650 cells rated for 20A discharge with 2 in parallel (or 2P configuration) that gives 40A total and I believe the trace fuse was rated for at least 40-50A on the pack as well. The 6Ah I am not sure which cells they used in them. With the fuse is hard to know for sure since it is simply a circuit board trace. I tried to use a calculator based on size and approx. Thickness of trace and it seemed to be close to 50A rating on the 5Ah. That is a lot of current. For reference the blowers pull up to 25A on turbo with my testing and the mower can pull up to 30A at times.

[@youtubular007]

@@ThriftyToolShed Thanks, that's helpful. If I put the two 6ah in 2P then I'll probably be safe (assuming they have at least as much discharge capacity as the 5ah you mentioned above). It may hit peaks higher than my estimate but hopefully the trace fuse can handle short bursts. It seems weird to me that EGO doesn't even supply this basic info.

[@trevorjames5493]

I fixed lb5800 blower for my friend thanks to your videos the problem was the mosfets. However he doesn't have a battery for the blower so actually tested it with a 56 volt ebike battery but I only hooked up positive negative my question is where would I connect the T and D blade terminals if there's only a positive and negative on the e-bike battery? They worked without the T&D but that was just for like a five-second test I don't think it would be good to leave them un hooked forever. It's getting a battery would be best but let's just say you can't get a battery and you have to use the e-bike battery where would you connect those? I was going to run one to positive and one to negative but the continuity test showed that none of them are connected at the input blades so I didn't want to try that. Thanks

[@ThriftyToolShed]

Awesome job. Yes the dreaded D-terminal..... I have a video called "What is the D-terminal?" and to be clear, I have not figured this out yet. The blower/tool will only run for about 10 secs and shutdown. I believe the terminal to be a one wire communication between the microcontrollers in the pack and tool. The only way I have found to get around it without EGO packs is the aftermarket packs. I have a couple review videos of these aftermarket packs because if nothing else I was super excited that the pack did have the correct communication with the tool to work properly. People have mixed feelings about them and I get that, but if you want another alternative to buying a EGO pack that is the only way I know of. So I at least appreciate that they cloned the microcontroller so the board works perfectly. I still feel it's better to buy a tool in a kit or bundle and get the EGO pack cheaper doing it that way. If you don't need a tool then the aftermarket is if nothing else is another option. Thanks for your comment. Best of luck to ya!

[@andrewroudny]

I just called in to the call centre for a bit of tech help. "D" is the discharge terminal. "T" is the over temp terminal.

[@kyleschraw7600]

Can anyone else confirm this or specify?

[@stevestone5524]

@@kyleschraw7600 I'm pretty sure the "D" terminal is DATA.

[@ThriftyToolShed]

DATA is what I have called it for some time. Not saying that is correct. I am positive "Discharge" terminal makes no sense at all..

[@luis789lr]

Do you know if its possible to solder a 10k ohm resistor to those wires if the battery charger would work without it having the thermistor board? I'm looking into making my own backpack battery pack and still use the ego bms for the tool and charger communications and a separate bms for discharging to protect the pack since i believe the current doesnt go through the ego bms.

[@btomas225]

How does one know what gen battery one is dealing with and which gen battery used the NTC 10k thermistor that can be read from the T terminal to ground?

[@ThriftyToolShed]

The 1st and 2nd Gen packs have a single LED for the fuel gauge. The 3rd gen has the segmented sectional fuel gauge LEDs.

[@DIYGuy85]

Does the charger need to read 10k between the T and the -ve terminal to turn on? I connected charger to completely different 14S pack and the charger would not come on. I'm trying to use Ego charger to charge custom 14S pack.

[@ThriftyToolShed]

I believe that is correct. It's been a while since I did the video "What is the T-terminal?" The older Gen 1 and 2 packs actually just had the NTC Thermistor across as mentioned in the video and the newer Gen3 with the segmented fuel gauge has a circuit with a transistor in it for the NTC.

[@jaybutler9797]

I have a battery with 56V+ but measures MOhms (Open) between Gnd and T terminal. It shows the Orange LED on latest gen batteries. Does that mean that Resistor RT2 in the terminal is bad or could be something on any of the pack? Thanks for your videos

[@ThriftyToolShed]

That would be the first thing I would check.

[@jaybutler9797]

@@ThriftyToolShed unfortunately the board is different compared to the Gen of this video. More crowded than any other board. I did not see anything in your most recent video with Gen 3 BMS about this 10kOhms. Thanks

[@ThriftyToolShed]

@@jaybutler9797 I do not have any Gen 3 of my own to learn much about. Just the one video as you had seen that a viewer sent one in. I don't have any mention of 10k on the newer Gen BMS board, but since it works with the exact same tools and charger that part should not be any different electrically even if the board layout is different. 10K.

[@jaybutler9797]

@@ThriftyToolShed I guess this BMS is different. I measured 2 new Gen 3 batteries and it shows the same 1.5MOhms between T and Gnd terminals. It might be different electrically speaking. I posted in the community. I will continue sharing over there my findings. Thanks

[@ThriftyToolShed]

The main difference appears to be a transistor in the circuit for the Gen 3 board. I have not had to look at the NTC on the newer boards at all yet. I looked at the only one I have here that is faulty and the NTC is just right of the middle of the board it's a black component that looks a lot like the ceramic caps except black in color. It has a via just under its right side and that goes back to the connector pin for the T-terminal. The other side of the NTC goes to the collector of a (1N) NPN transistor. The 1st and 2nd gen simply had the NTC across the negative and T-terminal. So it does not test the same unpowered, but the NTC is still in fact around 10K ohm at room temp. Hope it helps.

[@maxwhitley5860]

I fabricated a way for my kobalt 40 v weed eater to hold 2 20v batteries wired in series to make 40 v but on the inside of weed eater there is 3 contacts + and - what's the 3rd one for? My weed eater runs for a min then stops until I release the trigger and press it again then it runs for a minute and stops again over and over. I'm wondering if the 3rd contact has something to do with that.

[@ThriftyToolShed]

I believe so, the Kobalt packs have 4 terminals if I remember correctly. I have repaired 2 in the past, but did not go as far as looking into what the terminals do specifically. I seem to remember one having an Omega symbol which could mean Temperature resistance monitor and one was for Communication it seemed to me. Some tools like older Ryobi simply need the power terminals, but many need a communication with the pack these days.

[@Daltondoubledeuce]

My LM2100 has early gen 5ah battery that stops working after about 15 mins. Flashes orange I think, I’m colorblind. If I just take battery out and let it sit a few mins and put back in it works. Seems temp related. If I check between T fin and it’s around 10k is it the bms? And if it’s a thermistor, can I fix that with fuse like you soldered on? If so where can I get a 40amp small enough to fit? Thanks, love your vids.

[@ThriftyToolShed]

It could be the BMS or one of the many temp sensors on the board. The NTCs are easy to check and should be ok if reading around 10K at room temp, but it is 3 thermistors and also a temp monitoring board in-between the pack halves on the 4Ah and larger packs. I have seen way more loose connection issues than actual temp sensors bad. Thanks for your kind comment.

[@Daltondoubledeuce]

@@ThriftyToolShed thank you! It’s an early gen 5ah. Multimeter shows 53v and the resistance between neg and T is around 10k. Worth a look inside? What should I look for? Thx for answering me already.

[@ThriftyToolShed]

@@Daltondoubledeuce if it's orange I would check temp sensors and connections on them and if it is red it could be a cell pulling down below cut off level. So if you notice some being around 3.5V for example and one is reading below 3V you know that one will be an issue for you. They should be fairly close to being balanced.

[@pippenpippenger6759]

I melted my positive terminal and was trying to replace the whole terminal assembly. Do you know what that part is called or where I can get it?

[@ThriftyToolShed]

The only way I know of to get these is from a non-working pack from eBay etc. If you know a battery recycle place you may be able to get one that way. No way to purchase that I am aware of. I have even had communication with the aftermarket manufacturer of these type packs to see if I can eventually get parts from them, but no luck so far.

[@pippenpippenger6759]

@@ThriftyToolShed thank you

[@jaybutler9797]

Thank you

[@btomas225]

This is an old thread but I discovered in my newer (which is now completely dead) LM2130sp uses the T terminal (not the D) and thank god I found this thread because I had no idea what that terminal was used for. So, I'm back to square one troubleshooting my mower as I can't so much as even turn on the headlights. I've verified all the interlock switches and the handle harness. I've also checked the fuse but I still get NO sign of power anywhere. No led's light up, the self-propel doesn't work and of course the blade doesn't start. It's been a real head scratcher.

[@ThriftyToolShed]

I do not have the SP model, but know many suffer from broken wires in the fold of the handle. I do not fold mine and have not had that issue myself, but I did check that and mention it in the mower troubleshooting video I have. I ended up replacing the controller on mine, but hopefully yours is simple and maybe a broken wire, connection or interlock switch.

[@btomas225]

@@ThriftyToolShed Thanks, but I checked the harness in the handle. It's a 6 wire interface that appears to use serial comm between the electronics in the handle and the power unit. The interlock in the sliding part of the handle is wired to the handle where the bail and push button is. It has a board of some sort in the handle that takes the headlight switch, the button (that locks with the bail handle), the sliding handle interlock, the speed control buttons and the speed control for the self-propel function as inputs to it. The board has a single cable, 6 wire, that interfaces through the handle to one of the potted modules in the power unit. I do believe it's a serial link. I buzzed the cable and found no issues.

[@ThriftyToolShed]

That is a big difference from the older version for sure. If the fuse, all the interlocks and wiring is good then it possibly points to the controller board.

[@Daltondoubledeuce]

I have the LM2100 mower w/o self propelled. It just went totally dead. Checked continuity on wires from connector behind motor to handle, all good. Fuse good. It was the controller. Replaced it and back in biz, it’s a bitch to replace. Got controller from Power+Parts, around $100.

[@plojm123]

Can you just fake it and put a 10kohm resistor so you can charge with any diy charger?

[@ThriftyToolShed]

Well the T-terminal would not be hard to fake. The D-terminal to communicate with the BMS would be a issue. If you want the bms to monitor pack that is. You could actually charge with diy charger though if very careful and monitor the cells very well. The pack terminals for + and - go straight to cell connections. I always use constant current and Constant Voltage supply.

[@plojm123]

@@ThriftyToolShed I want to use a diy charger like you said but have the bms balance it and shut it off if a cell is to high

[@ThriftyToolShed]

Yeah, it communicates through the D-terminal for that. You would basically just need to get a 60V 5A supply that you could set for CV of 58V and set CC at around 1A and monitor each cell yourself to make sure they are balancing out ok. If the cells are in good condition, they will not drift much. We still have to always monitor and make sure.

[@plojm123]

@@ThriftyToolShed I do but to bad couldnt use what's there easily to take advantage of the bms

[@russellselkirk3956]

I just tried this with my dead new-style BA2800T and factory slow-charger. Batt test light would flash 2 greens for 1 pulse, then all red. Charger lamp showed overheat and would run forever. "T" terminal showed open so I soldered a 10k resistor from the blu wire to the large ground lug on the power board. With both "T" and "D" now showing 9.6k-ish, battery test light now flashes 3 greens, 2 greens, one green, then all red. No charging, oh well. If anyone runs across a box of new-style BCM boards let me know, I'd buy one!

[@kyleschraw7600]

So does the bms work without T terminal or D terminal being connected to ebike motor???

[@ThriftyToolShed]

The BMS will communicate with EGO tools so if using power terminals for e-bike, you will not have any BMS protection.

[@ThriftyToolShed]

Yes the tool requires the D-terminal. Most tools run about 10secs and shutdown if communication is not established between the tool and the pack.

[@stevemcgowan3017]

i have used 56volt battery on my ebike no problems but byoass bms as it had a fault.need new charger now though i used 48volt ebike charger will do same again.@@ThriftyToolShed

[@toddk63]

The thermistor on my BMS is reading 3.14 Mohm...so likely bad. What do I replace it with? NTC 10k...but what Beta?

[@ThriftyToolShed]

It seems the NTC is bad for sure. I simply share it is like the common NTC 10k at room temp. I have no way of knowing the beta than anyone else. I simply use spares I already have, I have not had to buy any myself.

[@toddk63]

@@ThriftyToolShed Thanks. if you or your subscribers are willing to post (in comments here) several kohm readings along with an ambient temp, I would be happy to plot and calculate a beta estimate. 0°C to 35°C would be a good range. There are probably two possible betas in the 10k NTC ~3435K and ~4000K.

[@matthiashamann6988]

Where is the NTC connected? To plus or minus?

[@ThriftyToolShed]

If you have the newer 3rd Gen pack with the segmented fuel gauge it will not read the same way as shown in this older video. It is a circuit on board on the newer BMS design.

[@toddk63]

@@matthiashamann6988 minus ground black

[@maxwhitley5860]

If your t or d terminal was not connecting to the tool terminal like weed eater would motor spin then shut off until you release and repress trigger

[@ThriftyToolShed]

Yes, for example as I have shared in some videos the blower will run for approx. 10 Secs and then cut out without the D-terminal connected. Releasing and then pressing the trigger again will repeat. The T-terminal is used by the charger, but not all tools.

[@maxwhitley5860]

@@ThriftyToolShed so how do I trick the tool through the d terminal

[@ThriftyToolShed]

@@maxwhitley5860 Excellent question. That is exactly what I was looking into and spent some time on and the 2 older video about the T-terminal and D-terminal was about the research I had done and I also mentioned that anyone willing to take it further would be awesome. I hit a road block of needing more time than I had to keep putting into it. I was hoping someone in the Electronics Engineering field could take it on as a project. Several viewers did contact me about going deeper into it than I had and most of these viewers seemed to be much more capable than I was on the EE side of it, but no real solution yet. Seems most have given up or at least like me no time to keep going with it.

[@maxwhitley5860]

@@ThriftyToolShed like I said I'm running 2 20 volt batteries off of my Craftsman tools to make 40 volts I'm assuming that since how they both have a d&t terminal that they both have their own battery brain so I hooked the d terminal from inside the weed eater to both the terminals on the Craftsman batteries. That was a no-go I'm assuming that's because I have two separate brains one in each battery and those brains are set up for 20 v and don't realize that they're tied together making 40

[@maxwhitley5860]

@@ThriftyToolShed thanks for your time and your help there's nothing else I have learned something