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Spaceweasel clicked Likes for this post: Sachs xtc 125 conversion by flo

10 Hours Ago

Electro Flyers replied to the thread An almost tragic lesson on charge controllers.
" Was the controller in direct sunlight or in the shade? Unfortunately, I don't see a temp rating for it. I've been through the cobbled together charging set-ups with PSes, and it seems now, in hindsight, it might have been a lot easier just to have gone with an environmentally rated, sealed, dedicated unit. Something like this one: http://www.thunderstruck-ev.com/tsm2...ontroller.html "

12 Hours Ago

cmcnall replied to the thread An almost tragic lesson on charge controllers.
" yes, other than the estop all switches are actually driving solid state relays with loads well under the rated voltage and current ratings. The estop has a magnetic blowout at 1000A. "

13 Hours Ago

Electro Flyers replied to the thread An almost tragic lesson on charge controllers.
" Thanks for the info. Basic ? Are your switches and relays rated for the DC V and A going through them? "

13 Hours Ago

cmcnall replied to the thread An almost tragic lesson on charge controllers.
" Attachment 7370
This is what I can remember. Basically it is as follows:
There is an estop on the battery that then connects everything.
The 12v dc/dc converter powers the avc.2 to handshake with the EVSE via the J1772 port.
It is always on and never disconnects the EVSE. When the EVSE is connected the chargers both are powered with the output of them in series and the output to the battery gated by a relay.
That relay is controlled by the charge controller that monitors the pack voltage. If the pack voltage is below the setting then it enables the relay. The charge controller is both powered by the 12v DC/DC converter when the key switch is on and by a 12V power supply then the EVSE is connected. This way the key doesn't need to be present to charge the bike.
The failure was in the electronics of the charge controller. It overheated in the sun and failed with all outputs high. Which is only a problem when charging and while it was suspect it was not understood that the cutoff would not work until after it was reached. I am not sure if someone makes a simple industrial over voltage cutoff relay but that would have simplified things quite a bit. "

16 Hours Ago

cmcnall replied to the thread The 3D Printing and Scanning corner.
" For anyone on a budget (<$300) and not needing a huge build area the printers from monoprice have served me really well over the last year. https://www.monoprice.com/pages/3d_printers
They are basically re branded Wanhao printers and have large community of users behind them. Just make sure to update the faulty heater board connections. "

17 Hours Ago

Listudus replied to the thread The 3D Printing and Scanning corner.
"
Quote Originally Posted by Jonny Panic View Post
I designed this printer and have seen it in person. The unfinished look of the part is not great, but that is due to them using nylon (much stronger than PLA), and it's got a bit of an ugly color. The parts are not nearly as "course" as they look in photograph, the print resolution is actually very good. I used a wrench they printed with carbon fibers embedded, and it's pretty impressive how rigid they made the part.
Yeah, I heard about this printer too, and I read about it on http://3dinsider.com/3d-printers-for-sale/
As I can remember, this printer was among the most cheapest printers ever, despite it's innovative technology.. "

2 Days Ago

Electro Flyers replied to the thread An almost tragic lesson on charge controllers.
" Could you show a schematic of your charging set-up? "

2 Days Ago

Nicman replied to the thread Nic's Kawasaki Ninja 250 EV conversion.
" Finished wiring the contactor and controller to the kill switch today, and took it for my first ride. This thing is scary quick! I'll be wiring the 12v system in the coming days/weeks while practicing before getting my motorcycle endorsement. Thanks everyone for all the help along the way.

Pics to come when the finishing touches are all in place.


Sent from my iPhone using Tapatalk "

2 Days Ago

flo replied to the thread Sachs xtc 125 conversion.
" HI,
Well these cells would have fit perfect into the space within the framework and i like the idea of bottom ballancing lifepos.
I guess i will not use a hub motor for reusing my wheel that i already have and i do not like the idea of the undampened mass.
Unfortunately we do not have any resellers of nissan leaf type of batts here in germany. Guess it all is directly recycled by the mfg to keep public from a good deal...how dare we to buy used.
Would not even dare to ask shipping lipos from usa, cost hazzle....

thanks for your input though

greets

flo "

2 Days Ago

marcexec clicked Likes for this post: An almost tragic lesson on charge controllers by cmcnall

2 Days Ago

marcexec replied to the thread Sachs xtc 125 conversion.
" Consider using a hub motor - it frees up loads of space. Check my signature for my thread.
LeFePo4 is kind of left behind since we got access to OEM class large format cells, I'd have a look for Opel Ampera cells (Volt in the US) from a breaker or Leaf (60AH might be a bit much, though). "

2 Days Ago

marcexec clicked Likes for this post: Sachs xtc 125 conversion by flo

2 Days Ago

marcexec clicked Likes for this post: Sachs xtc 125 conversion by flo

2 Days Ago

flo replied to the thread Sachs xtc 125 conversion.
" Forgot to even take pics when i got it so here is what they normally look like:

greets

flo "

2 Days Ago

flo created the thread Sachs xtc 125 conversion.
" Hi everyone.
Been reading and book-marking all i could find about ev conversions on motorbikes since i had a test drive in my buddies BMW i3 electric car.
Instantly wanted one, but my wallet just isn`t up to it.

So a Zero or the like would be nice as well but frankly ... still kind of expensive over here in germany.

A conversion on the other hand might be just within reach. Especially if it stays within the envelope of what i want it for.
Having build my own design electric rc planes for at least 30 Years i found that there is hardly a difference between an e drive for motorcycles and planes apart the difference in power and Voltage, as well as the MOT ( i belive that is what it`s called - it is the "TÜV" over here we have to deal with) to make it street leagal.
Having a quite capable OD-DIY cnc shoud help somewhat as well. If only to remaind me that i managed that as well .

So-
The Goal:

Having had my fair share of big/heavy and powerful motorbikes i always enjoy riding my trusty 81`SR500 that i own since 28 Years.. lately i had more and more been leaning towards smaller and light(footed) bikes to ride the small country roads surrounding my village. Might be an age thing but i just do not need a big travel bike anymore.. Sold all my big ones, leaving me with my trusty SR
So i want a motorbike to be used like your regular scooter, bakery, shops, lake, quick trip to city, commute to work (35 km 21 mil one way - i can charge there) or a run around the fields for an hour.
So highway speeds not strictly neccesary but it should top out above 100 km as not to be a nuisance to other drivers and certainly i do not want to get overtaken by trucks all the time (90 kph).
In order to get all over town i need aprox 80-90 km max distance ( slow riding) with onboard charging if i go over half of my amperage...
What i really want is a bike that has a bit of "grunt" - no need to out-do a 750 but being used to my old SR, acceleration should be within say 7-8 ish sec to 100 kph.
So reasonable preformance no outstanding needet.

The bike:
As stated before i want a nimble, smallish bike and i do prefer your typical sportbike. So instead of sourcing a say 600 or even 1000 cc donor bike to end up lighter when done, i figured to use a small type that may gain a few kg in the process but still stays lighter in the end and than the other way.
Most conversions of bigger bikes end up somewhere in the neighborhood of 190 kg whereas a tiny bike could end up say at 150kg. (assuming lifepo4 batts).

As there is no need to reinvent the wheel i figured i use following items:
-Me1115Motor
I was hoping to use 25S72Ah Lifepo (these: https://www.ev-power.eu/index.php?cu...disc&anid=4490 ) which would have been perfect just to find out today that these had been discontinued. Perfect sice match and capacity easy to mount ... bummer.
-svencon controller
-throttle tbdt.
-kp 1200W charger for weight reason... maybe the 1500w one - depends
-most likely to run a seperate 12 V system as it is required anyway to make the bike street legal.

The plan:
Already got the donor bike and de iced it last two mornings.
Wanted to make templates during the course of this summer ... need some time to save up some money.
Try to do the build during the early winter and build the bat. in winter. too..
comes spring i would like to be ready to test it and make it street legal by summer.
Most likely this won`t work out as already now i need to completely change my battery setup which would have fitted perfectly.. grrrr.


Anyway that `s it for the moment, if anyone has a source for this bats, preferrably in EU...let me know

Some pics as well:

The bike with all needet and all ice removed but with tank is 79 kg as seen in pic its 72kg "

2 Days Ago

ElMotoMike replied to the thread An almost tragic lesson on charge controllers.
" "

3 Days Ago

ElMotoMike clicked Likes for this post: An almost tragic lesson on charge controllers by cmcnall

3 Days Ago

Hugues replied to the thread An almost tragic lesson on charge controllers.
" thanks for sharing "

3 Days Ago

cmcnall created the thread An almost tragic lesson on charge controllers.
" Hey all, wanted to share an almost tragic lesson in trusting a crappy voltage cutoff controller from ebay.
I have a 24 cell chevy volt module on my bike with cell logs on each cell so i can monitor the individual voltages. I plug a ballencer in every month or two and balance the cells when needed.
The other day I parked my bike in the hot utah sun while charging. I get back and notice that the LCD display is garbled and the LEDs are all lit.
The unit in question is this one: http://www.ebay.com/itm/DC-Programma...YAAOSwagdXRsqA
I usually charge to about 98v and have my meanwell supplies set to about 99V. Well turns out the controller died with all outputs on, IE charging my cells and not cutting off at 98V!
So i didn't really think much about it and get home and plug in the charger and charge all night not knowing the Outputs are stuck on. I get up and find my cell logs yelling at me that 2+ cells are charged to 4.35v!
I'm not sure how tolerant the LIMN02 cells are to overcharging but I think I'm lucky to not have a fire.

So.. takeaways for anyone reading this.
Keep your chargers max voltage low if you have a crappy charge cutoff and if it dies on you, your battery won't overcharge.
Consider getting a truly industrial rated meter. Even having a balancing circuit may not have helped this as the charging current was much higher than any balancing load could supply.
Perhaps add redundant cutoff relays. I could have tied the alarm output from the cell logs to the charge circuit.
Consider extreme heat on the longevity of you control electronics.

Not sure what else to take away from this, but please add your constructive advice below for others.
Also anyone think I killed my cells? I have done a few more rides since then and haven't seen any major loss in capacity but still concerned. "

3 Days Ago