All New Micro LVC for Turnigy 6S

[Knuckles]

All New Micro LVC for Turnigy 6S!

Micro-LVC.jpg (24.57 KiB) Viewed 1407 times

Just plug in to the JST balancing leads of a 6S LiPo and connect it to your ebrake circuit.

T5000-6-20.jpg

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Available at "Fantasy.Land.com"

[vanilla ice]

I'll take two.

[AmpEater]

How much for a 8s version? I'd take 10

[mwkeefer]

Y have you been hanging out with Amberwolf cause your photoshopping is getting better?

PS: You should put a cart page up for these just for shits and giggles, wonder how many would bite.

-Mike

[Knuckles]

I am hoping LORD G-G-G-G-GOODRUM will build it!

BEFORE ...

Before.jpg (166.01 KiB) Viewed 1356 times

AFTER ...

[GGoodrum]

I am hoping LORD G-G-G-G-GOODRUM will build it!

BEFORE ...

Before.jpg

AFTER ...

Soon.

[mwkeefer]

Gary,

you should make Y solder all the micros, careful what u wish for
-Mike

[Knuckles]

HAPPY HAPPY JOY JOY

[amberwolf]

Y have you been hanging out with Amberwolf cause your photoshopping is getting better?

I"m pretty sure hanging out with me for PS skillzors would lower anyone's capability as they get infected with whatever causes me such grief with it.

Oh, right...lack of time and lack of true desire to make it look better. More the latter than the former. "gud enuf" is my usual motto.

[vanilla ice]

Could you not build something like this with the buzzer output from the existing HK monitors? I don't speak electronics, but it seems like It'd be easy.. Simple add on circuit right? Buzzer leads get voltage, brake cutout gets triggered.

[fechter]

Shitcan the ILD2s. There are much less expensive ones that will work fine.

Some of these alternates may have a different pin configuration.

MCT9001_Q
MCT6H
LTV-826
LTV-826s (surface mount version)
ACPL-827-360E (surface mount)

Yes, a small beeper/buzzer could run directly off the output. Would you hear it? (I wouldn't)

[Knuckles]

Close Up

Side by Side

[Metallover]

All today's lipos really need is a low voltage cutoff and overvoltage protection. As long as the cells don't go under 3v/cell or over 4.2v/cell, they will be fine.

The solution to managing lipos is below. The packs shouldn't need to be balanced too much, but every lipo user should have a balancer that they can hook up and individually balance a pack if needed. Each one of these devices will be networked to the controller or something similar.



Price - <$5 each

There is no need for a fancy self-balancing expensive bms. It would be nice to have, but if you can have something that won't let you ruin your packs for 1/4 or less the price of a proper bms, you need to go with that.

[Knuckles]

You missed the point!

It MUST ALSO connect to the CONTROLLER! Like with the ebrake circuit!

T6S-Monitor.jpg (90.26 KiB) Viewed 1137 times

[geoff57]

hi
Knuckles started this thread as a result of me telling him that I was thinking of doing a SMD version of Garys LVC/HVC boards.
I have since compleated the artwork on that board and then got thrown a curve ball when I find out that Gary is going to start playing with the HVC settings, by this time i had been talking to some people outside of the forum and found that the part of Garys circuit that is most wanted is the LVC circuit. The parallel balance board can be made with a piece of stripboard if needed and you can choose how many packs you put in parallel.
I then desided to go down a difrent route for now at least and make the micro LVC or thumbnail LVC a reality, I had previously got a LVC board from Gary and so used it as the blueprint for the circuit design, if it worked for him it should work for me, once the circuit design was drawn on paper I started to draw the circuit board in the computer. after I had a working model in the computer it was time to compress it as much as I could Size was important to me for this project.
Once all the copper had been placed where it had to go I started on the top and bottom text, not needed but it adds that little extra to a PCB so I thought I should put it in.
I then got the computer to export all the files that any PCB factory would need.

Now comes the hard part I am getting the boards made in china, my contact Keywin Who supplys a lot of the infineon controllers has a PCB factory handy and we are working together to get the first batch made as soon as we just need to find out what if anything is missing from the list of files I sent.

Now we come to the good part the what it looks like.
The board will be 38mm by 25 mm
it will have a 90 degree JST connector on the input and one on the output along the 25mm side
there will be a pair of 2 way jst sm connector pigtails for the LVC trip output simmilar to how gary does his setup
there will be no parts to put together as all that needs to be added to the board is the 2 connectors and the 2 pigtails both of which I am going to get keywin to do once things are underway, he will do 5 cell and 6 cell from the start other sizes will be offered as kits the more people that want a size the more chance that cell size can be made up not in just kit form, there is pcb board under the connector housing to add strength.
as for price I cannot say yet I am still waiting to hear back from the factory as to the cost of the first run and the cost of future runs using the same templates as the templates are the bit that costs the money.
I have a few pictures of the PCB design for you to look at below
first the circuit board much like you get from Gary

top and bottom tracks.jpg (55.56 KiB) Viewed 1057 times

next the top overlay this is mainly to place the components

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finaly the botom overlay for this I had to put it on the board in mirror format so it would come out correct i have reversed the image for you so you can read it

bottom overlay.jpg (35.26 KiB) Viewed 1055 times

I will post an idea of the price as soon as I can.

As you will See there is a copyright on the back of the board but it is only for the SMD design work the circuit I think we can consider is open scorce.

Geoff

[Gregory]

Geoff, I think I saw you post that the first batch is for UK only.

I'm keen for 4 of the 5S in Australia ASAP. I'm ready to drop in an easy LVC solution into my bike.
Thanks.

[heathyoung]

I've been working on this as well. The 12S I have for the Konion pack I have in progress is 25mm by 35mm and is single sided so no vias or through hole plating (so board costs are considerably reduced). The trick is to use both through hole and SMD parts (and design PCBs as part of your job too I suppose)

And there is a 24S planned as well that is 25 X 62mm. Oh and in Aus as well.

[Tiberius]

Geoff,

You mean something like this? This is an 8S LVC I made some time ago for my Headway packs.

LVCa129.jpg

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http://endless-sphere.com/forums/viewtopic.php?f=14&t=10494

Nick

[heathyoung]

Yeah pretty much - I used dual opto isolators in a SOIC-8 package rather than single packages, and it looks like you used a bridge rectifier so you didn't have to worry about the polarity of the ebrake line. At work we do boards in house, so at least I don't have to farm it out - looks like a decent house did yours, soldermasked and everything

I get the idea of using through-hole, its easier for non-smd people to assemble, I regularly work on really small stuff, but when I design I rarely go under SOIC and SOT-23 unless I have to.

[geoff57]

hi
Gregory I did not quite say the UK the first batch is for europe there are some motorbike guys in Italy that are showing interest and ththe first batch will be small and I want quite a few for my own lipos about 4 KWh at 4 boards per KWh as soon as the first batch passes the tests we will do a second higher production run these will be made avalible through any one that buys from keywin / Ecrazyman so look for your local infineon dealer and ask him if he is supplied by keywin/ecrazyman.

Heathyoung a 12 channel board for Konion LiMn cells I belive, I don't know what the LVC of that type of cell is I have never used them. If you look at my design you will see there are no links between the top and the bottom of the board except for the parallel tracks on the back that link the input connector to the output connector, if this was just a end connection LVC it would be smaller about 34 mm by 25 mm but I felt an output connector would be important. I don't do PCB design for a living but i did get software that would help me but in the distant past when windows was not around I did do PCB design work and have never forgotten the basics though back then it was single sided and SMD was unheard of. the nice thing about this design is that if you can find a LVC value for the TC54 component that will work with the battery you have all that is needed is to have the factory replace the tc54 component with a diffrent one in the same family I know ther is one for LiFePo4 and inthe future I will be exploring doing that but I dont know about LiMn.the size to some degree was dictated by the connector that was chosen to match with the balance connector on the LiPo battery packs from hobbyking the boards primary target.

Tiberius I like it nice job there I went on to your thread to have a read of what you did. With my LVC I basicly did a copy of Garys design with SMD components but you have come up with a design that looks original mine uses the sot 23 package of the TC54 but from what I can see you are not using a TC54 as the only other SMD package is the sot 89 and that has only 4 legs not the 5 that are on your component, i recognise the resistors and row of opto isolators but what are the components above the optos for, I am always up for improving things if it is relivent. I will be using the same type of output connector from the optos as you have though like fechter said I will have 2 to allow for easy daisy chaining. price has had to be a considaration with me and I can get the through hole 90 degree connectors for a good price but i agree with you there should be no way that a load of sharp spikes can dammage a LiPo pack so the best idea I have is to cover the board from connector to connector with heat shrink tubing clear if possible I know I can put clear in but getting keywin to is a diffrent matter. As I have said before I will add other board types to the range if this one takes off, starting with 8 cell LiPo LVC then following up with 8 cell LiFePo4 LVC they will all be fitted with similar connectors or suplied in kit form if you do not want to use the connectors.

I started off just doing this becaus I did not like the Idea of buying all the boards that would be needed for the LiPo battery packs I have got and then have to populate them all with components check them and anything else that would be needed.

Heathyoung I see you have explained what the components above the optos are for thanks for that, my soloution was to put text on the board and to color (sorry to those in the UK) code the output connectors to hopfully get things correct. BTW I also went for a duel opto package the SOIC-8 the SMD version of the ILD2.
Its ok doing it in house for yourself if you just have a few to do but I did not have that avalible to me so farming out was my only option now china may seam like a long way to go but I know they do things cheap there, the first board I sent over for the factory to giv me a price on was a SMD copy of Garys LVC/HVC boards with 4 way balancer and a connection holes for the battery medic booster a more or less exact copy but with SMD components so much less soldering required the cost of a board from Gary is $10 the mouser parts are $10 the non mouser parts are $15 these would be the balance connector housings the 2 way pigtail for the brake output and the 7 way pigtail and connector to the battery medic booster box, a compleat kit would cost $35 for everything including the PCB but that would still require it to be put together, I was given a price for 10 boards(still not enough for all my lipos but would go a long way to getting there) this was going to work out at less than 10 kits, to this I would have had to add the output pigtails which I have plenty of, housings for the balance wire connectors also of which i have plenty of and can get more of from keywin for a very good price the battery medic booster pigtail would be a bit of a problem but I helped Gary get the crimped connectors for the molex pigtails so all i would need would be the connector housings from digikey and a load of wires with crimps for the connector fitted to the end from keywin in all the total cost would work out at most the same as 10 boards from gary BUT the big saveing is that I would not have to solder all of those components onto the boards, as a byproduct future orders would cost less as the factory would already have the masks but the quantitys I would have to order would have to be that much bigger, I never did find out how much a future order of these boards would be as my aims changed.

thas all for now
Geoff

[momo]

That LVC would be perfect, I could use a few of those.

[philf]

Sheesh. I just can't keep up with this place. Really. I just started playing with LiPo this summer, after wading in (deep) to all that's been posted here on ES. I finally gave up and just started playing.

I hit the same poser that everybody else does - what do you do for a BMS? Then, realizing that the chargers I'm using look after the ugliest task, I was taken by the elegance of Gary's solution for pulling the e-brake low when any cell hit 3V. Brilliant - I placed my order with Digi-Key right away, and went to work on a board - I wanted it to look after a 12 cell pack. Meanwhile Knuckles started this thread (synronicity!).

Here's the board:



It had to meet two special criteria - it had to fit in a small Hammond box, and I really felt I could make it SINGLE SIDED. And I did.

For giggles, I added an extra resistor and an LED to each channel. Funny thing to do - when any cell is over 3V, the draw of the circuit is in the micro-amp range. When you get down to the LVC, not only is the opto-isolator activated, but the LED glows. The draw is 9ma. Obviously something you wouldn't leave plugged into the pack at this point, but I thought it would be useful to see WHICH cell is pulling the e-brake. In a perfect world, when you're finally "dead", you'd look at the board and see 12 LEDs alight. In reality, I'm sure there's ultimately gonna be one cell that goes first - and it would be nice to be able to glance and see if it's always the same one. Dunno if this is gonna be useful or not. We'll find out.

Populated, it looks like this:



After doing a quick Dremel job to round out the corners for the Hammond box (my drill press snapped its belt while I was building this), I realized that the box was probably overkill. So I stuck the whole affair inside a piece of clear heat shrink tubing and just stuck it to the pack with Velcro. (It would have been tidier if I hadn't taken out the corners, and if I hadn't hit the tubing with the heat again after cutting out the connector hole).



Will post about the usefulness of those LEDs when I can get out for a good run. We've been living with torrential rain for the last few days. No fun.

[geoff57]

Sheesh. I just can't keep up with this place. Really. I just started playing with LiPo this summer, after wading in (deep) to all that's been posted here on ES. I finally gave up and just started playing.

I hit the same poser that everybody else does - what do you do for a BMS? Then, realizing that the chargers I'm using look after the ugliest task, I was taken by the elegance of Gary's solution for pulling the e-brake low when any cell hit 3V. Brilliant - I placed my order with Digi-Key right away, and went to work on a board - I wanted it to look after a 12 cell pack. Meanwhile Knuckles started this thread (synronicity!).

Here's the board:



It had to meet two special criteria - it had to fit in a small Hammond box, and I really felt I could make it SINGLE SIDED. And I did.

For giggles, I added an extra resistor and an LED to each channel. Funny thing to do - when any cell is over 3V, the draw of the circuit is in the micro-amp range. When you get down to the LVC, not only is the opto-isolator activated, but the LED glows. The draw is 9ma. Obviously something you wouldn't leave plugged into the pack at this point, but I thought it would be useful to see WHICH cell is pulling the e-brake. In a perfect world, when you're finally "dead", you'd look at the board and see 12 LEDs alight. In reality, I'm sure there's ultimately gonna be one cell that goes first - and it would be nice to be able to glance and see if it's always the same one. Dunno if this is gonna be useful or not. We'll find out.

Populated, it looks like this:



After doing a quick Dremel job to round out the corners for the Hammond box (my drill press snapped its belt while I was building this), I realized that the box was probably overkill. So I stuck the whole affair inside a piece of clear heat shrink tubing and just stuck it to the pack with Velcro. (It would have been tidier if I hadn't taken out the corners, and if I hadn't hit the tubing with the heat again after cutting out the connector hole).



Will post about the usefulness of those LEDs when I can get out for a good run. We've been living with torrential rain for the last few days. No fun.

hi Philf
been a long time since I have come across a post from you glad to see you are still working with SMD work.
good work was it a home etching or did you get someone to etch it for you, the LED's are a nice touch but the only time the LVC kicks in generally under load and when the load is not on the LVC kicks out so you probably will not be able to tell which cell has gone low when you come to look at the LVC more than likely all the LED's will be off, the Idea is good but the method of doing it I don't think will work, for it to work the voltage of a cell would have to still be below 3V once the bike had stopped that would make the under load voltage dangerously low so not the way to go. If you want to try this Idea to recognise which cell has gone low and I can see some logic in it what is needed is a way to lock the LED's that go on so they stay on until the LVC can be checked when the bike is still I am sure it could be done with transistors I should know what sort of a circuit to do but on a sunday I am only half awake I will come up with something later.

With the LVC I have done size was important it was to cover only one pack per board(you could of course add packs in parallel) the boards are to be put inside cases so cell low LED indicators were not important though I do think it is a idea to think about for future projects, for now I will rely on when the bike is home and the battery pack is ready for charging the cells are checked with a cellog8 or similar device or if you are charging with a R/C charger you can use the cell voltage monitor that comes with it. We must also think in terms of the fact that since the turnigy packs and zippy packs are not easy to take apart I have tried finding a bad cell is not that useful but finding a bad pack would be as this is the only thing that can be changed for those that have made 6S packs from 3S packs a single LED on each board would not be a good idea but as there are not that many that have taken that route a single LED should be enough that will identify the pack or group of parallel packs the worse pack can then be identified by separating and reading the pack voltages or you could fit a LVC with LED indicator to each pack for a few rides that should find the guilty one.

Thank you philf I will be leaving this version as it is but I will be doing a future version that can identify if a pack has a cell that keeps going low first or I may go for cell detection I am not sure for LiPo only pack detection is needed but for LiFePo4 say with A123 cells cell detection would be useful, but I am not going to be doing the LiPo4 version yet.

Geoff

[heathyoung]

I thought about the LED on my boards as well, the increased forward voltage will stop the cell discharging to 1.2V through the optocoupler, but rather down to the Vf of the LED and the Vf of the optocoupler. This is a good thing.

The cells that are down will probably only stay down under load, so you would need to latch with an SCR - as soon as you remove the load, it will probably clear depending on how quickly the cells recover.

The failure mode of the TC54's is of some convern as well - they fail shorted, so will drain the cell to the VF of the opto LED.

Also - quick question - what are you using for tinning your boards? I've been trying to find something cheap that works well, TINNIT is not available in Aus, so I've almost resorted to making my own with Stannous Chloride 5 grams/litre, Sulphuric Acid (66 Be - 96%) 10 ml/litre and Thiourea 50 grams/litre.

[philf]

Also - quick question - what are you using for tinning your boards? I've been trying to find something cheap that works well, TINNIT is not available in Aus, so I've almost resorted to making my own with Stannous Chloride 5 grams/litre, Sulphuric Acid (66 Be - 96%) 10 ml/litre and Thiourea 50 grams/litre.

Wow! That's some chemistry . I use a product from MG Chemicals called "Liquid Tin". Actually, all of the materials I'm using to make PCBs are MG Chemicals products, from the pre-sensitized boards, developer, and etchant, to the film I laser print the artwork on to. The system rocks.

But! I gotta say it... Like geoff57, I didn't think there would be much to see when the board tripped. Was I wrong! The cells did rise back to above 3V again, but stayed low long enough (well over a minute) for me to grab this shot on the first exhaustion.



I confess, this was after an artificial depletion through my "load bank" (a scaleable array of 500w halogen tubes)...



So, I charged up and took the pack for a real ride and... Alison had to take my picture being all excited (yeah, that's what I look like when I'm excited) after I chased through the house still holding the pack with an LED lit (there were two when I started looking for her).



I'm frankly stunned that it works so well.