DID I SCREW UP??????

[pkirkll]

Thanks!

I had a weird feeling about my schematic.....i am glad you posted up....i am at a hobby shop now and i think he can make up a harness...... or i may just go with 5 batteries for now and order the harness from icetea....lol

 

[mark5]

Cheeseboy's diagram is what you need. Since I also drew one it's included below.

That's making 5 parallel groups first and then connecting them in series.

View attachment 1

Another way to do it is making 5-pack series groups like the jkbrigman trial battery mentioned earlier and then connecting them in parallel. You can use a ready-made parallel cable like this
http://epbuddy.com/index.php?main_page=product_info&cPath=26_14&products_id=201
to make the paralleling Y connections on the left and right sides. Maybe your hobby shop has a cable like that.

 

[pkirkll]

The Five Pack SeriesGroup IsOkWithMe ...... AreTheValuesThe Same....InTheEnd

 

[Cheeseboy]

Yeah the difference is you have two 10s 2p blocks instead of five 2s4p blocks

The convention is to Parallel first, then series, as this allows the parallel packs to remain in balance with less wiring...

If you go series first, simply make two 10s2p packs (your series block in your original drawing) and connect those in parallel. Again, paralleling the balance taps of each corresponding cell is important to ensure the parallel packs remain balanced. However, if you split the pack into its two 10s2p blocks and balance charge each series string individually it is not required.

Both ways end up being 10s4p, or 37v 12Ah.

 

[mark5]

The Five Pack SeriesGroup IsOkWithMe ...... AreTheValuesThe Same....InTheEnd

The values would be the same. Some people here do it that way. But back to the other way.

Some real-life pictures of the paralleling first then series connecting way that Cheeseboy's diagram shows can be seen in dogman's review of icecube57's harness:

dogman: Icecube 57's Lipo battery harness review. 4 battery set.
http://endless-sphere.com/forums/viewtopic.php?f=4&t=32096

That harness has 2 groups of 2 packs. You'd want 5 groups of 2 packs. But in the first picture do you see how easily he can convert from discharging to charging by just using the series connect block vs the parallel connect block.

 

[pkirkll]

Here is how we wired up the controller so i could hook up the hub---and the batteries-- i used a Y-connector so i could use either the 5 pack by itself or both 5 packs at once...

AND i got a picture of the hub brushes the guy gave me as spares,,, i forgot i had them ...sorry....

i will hook up the wheel tomorrow and see what happens!!!!1

Please look at this and tell me if i can hook it up like this with this Y connector to the controller---- each Y would be receiving a 5 pack built in series....

So i will have one bank of 5 packs in series and another bank of 5 packs in series...Y'ed together in parallel right before the controller

Hooking everything up in parallel 2 packs at a time was confusing to me right now,,,series is easy and i dont need an addition wiring harness... i will work on learning about the benefits of the parallel building, but right now i just wanna see the thing turn!!!!!

 

[pkirkll]

oops, forgot the picture with the brush assembly

 

[Beachcruzer]

Yeah, that'll work. Enjoy your ride.

 

[pkirkll]

Thanks so much to all of you for your suggestions!!!

I am looking forward to spinning tomorrow!

paul

 

[dogman dan]

Back up a miniute, and read about toruqe arms, and how to fit the motor to the forks.

My first ride lasted one minuite, the motor left the forks, the wires to the motor cut and shorted, which blew the controller. The key thing is the fit of the washers, they can't be too big for the cup in the forks. That was with 35 amps of power, you are going to have triple that.

YOU ARE CONTEMPLATING A 3600W FRONT HUB BIKE!!!!! I'm one of the few guys here that was ever crazy enough to try it. To ride mine, I put on a DOT helmet, kevlar gloves, and leathers.



Re melting the motor. What happens with motors is this. If you are climbing a steep enough hill, the motor slows down. By the time you are traveling at less than 15 mph, at full throttle, you will have much less efficiency than normal. What this means is more of your power is making heat. So by the time you reach 15 mph up that hill, you might be turning 33% of that power into heat.

So do the math. The motor was designed to use a 35amp controller at 36v. 35x36 is 1260 watts of power. So up a steep hill you might be running a 420 watt heater inside that motor. Ever tried to put your hand on a 500w halogen bulb that was burning? Pretty hot eh?

Now do the math on your rig. 100 amps x 36v. 3600w. 33% of that would be 1200 watts of heat. So if you climb steep hills, you have the potential to melt that motor down very quiclkly.

Bear in mind that brushed motors melt easier than brushless ones. Brushes just turn into arc lights when you run enough power through them melting the plastic brush holders. Then the epoxy on your magnets loosens and the magnets inside start wandering.

How do I know this shit? I have done it, with just 1000w.

 

[pkirkll]

WOW,
I didnt think about the amount of amps thru the controller,,,

I dont understand yet where 1oo amps are coming from.....i have 6aH batterries with a total of 12aH available, but the controller is set for 30-100 amps.....would it be true to say that i have to crank the throttle wide open to get 100 amps to the motor...and if that is true could i keep the throttle backed off to reduce amperage???

I have red a lot about the torque arms -- what do you think about the torque washer things? I have them available....

I didnt realize i was getting this build up to such high wattage with so few batteries.....they are so small and light they dont look imposing... i will wait for your reply before i "Pull the trigger"---

going down to the bike shop now,,,will send before and after pics!!!!

Thanks for the warnings... i really do appreciate them.

paul

 

[pkirkll]

I guess the thread title should change to "Have I screwed up yet!"

 

[999zip999]

Beachcruser has a beach cruser at 3500watts front hub with kick brakes A fun ? ride at 32mph. Now let's trade back. Wow. Lipo and front wheel drive and a high limted controller. What are you thinking ? Alumiun frorks ?

 

[dogman dan]

Back to basics.

Your batteries are measured in amp hours. amp hours measures capacity, like how much water can fit in a bucket. amp hours x volts = watts

Your controller is rated in amps. Amps is like how fast your water comes out through a hole in the bucket. Didn't you say you bought a 100 amp controller?

Your battery is capable of discharging a certain amount of amps without damage. You bought the kind that can put out 100 amps of power.

So if you hook batteries capable of 100 amps discharge, to a 100 amp controller, your motor will see 100 amps. 100 amps x 36v = 3600 watts. Into a motor designed for about 800. It can be done, but it's flip a coin which happens first, the wheel flies off the bike, or the motor melts.

fun stuff though.

 

[dogman dan]

On the other hand, that's a pretty small looking controller for 100 amps.

What does it say on the label? Looks to me more like 50 amps or less just guessing by it's size. But it's got serious heat fins, so maybe it is 100 amps.

 

[pkirkll]

Dogman,
It is rated from 30-100amps i think..
I have spec sheet in an earlier post...i will copy that here.... http://www.tncscooters.com/YK43B.php

How can I tell that my batterries are capable of putting out 100 amp discharge...by the 25C nomenclature.....

Basics..... first thing i did today was hook one of my batteries to itself,,,touched red to black!!!!! Goober would not have been happy!
On the plus side it only touched for a zilliiiiiisecond....

I did get it on the bench in our homemade "front fork in the vise trick"...then i steped off as far as the throttle cable would allow and started cranking it slowly .... and POOF,,,it started turnng and turning pretty smooth and easy,,,,,(with 5 battery packs) 10s1p right?....

I am going out in a minute and put it on my bike---i just got it off the build rack at the shop and it turned out nice! Kona with FS....CRO-MO fork,,,,lol---- i dont have any torque arms yet so i will go very easy...... here is one picture of the donor bike in the rack---

 

[Beachcruzer]

The description says 30-100 amps. I suggest calling TNC scooters and asking if the amperage limit is adjustable, though that seems like a bit of a long shot. Dogman knows better than me, but it seems doubtful that you'd smoke the motor instantly unless you give it full throttle on a steep hill. Cooking a motor normally takes a little bit of time, like barbecuing a steak. I would treat it as a "pedal first" controller to start with, making sure the bike is rolling before you ease on the throttle. As you get used to the bike, stop and feel the motor from time to time. If it gets warm, proceed with caution. If it gets hot, stop and let it cool down.

If I were in your shoes, I'd put this rig together (with torque arms) and see what this ebike game is all about. You'll probably want to change the motor and controller at some point, which you can do for a fairly reasonable cost if you know what to look for. But give this one a chance first. Don't buy the first thing that comes along to replace it.

The "C-rate" is a multiplier. You multiply "C" x the amp-hours to get the maximum discharge in amps. So, 25x12=300 amps. You multiply the amps by the voltage to get max watts: 300x42=12,600 watts. That's the max potential of your batteries, which would fry your motor in a heartbeat. Through that 100 amp controller, you're going to feed a max of 4,200 watts (100 amps x 42 volts). That'll smoke it too, just will take a bit longer.

Cool bike.

 

[pkirkll]

Well I rode it this evening.......finally got it put together good enough to take a test run.... nothing blew up and the motor was only slightly warm after i just finished a hard crank on it to see how fast it would go.

I think you are right about watching and learning with this motor...gotta start somewhere...i can always sell these 2 banks of 5 batteries separate for a lcal commuter...then i can get some peally powerful stuff!!! hahahaha

I didnt realize that i was getting so amped up with this build with these small batteries..... i have a lots of respect for them now,,,they hauled my butt at 23 miles/hr....[no where close to the 30mph i had heard...but i am big 260 ~~~~]

This otor has already ben abused ,,,it makes a funning hmmm noise when it first starts running.......the guy i got it from used 12 volt SLA battery----and get this-----a light switch from Home depot for 69 cents as a throttle!!!!!!!! hejust flipped it back and forth,,no controller at all.....it is amazing it runs at all...

I was using only 5 batteries for my test,,,but that is still the same amount of power right? Just not as much "gas in my tank" as if i had had the others wired in.

I have a copy of my ride on My Tracks android app...it is pretty cool..tells you all about your ride or walk,,,elevation ..speed..ave speed while moving---(case you take a break),,,highest speed and a graph,,, i will try to make a link and put it in here,,,you can tell i was having fun by how i was riding around like a crazy man...

https://maps.google.com/maps/ms?msa=0&msid=217594939461474197158.0004cd63da1b07f8ef8c1

Click on the word END over in the left column on the bottom and you will see how much data is logged...
23.74 mph top speed---14 average.. i have never pedal that fast----- i ran out of gears on this way too fast,,,i couldnt help at all up around 16 mph...

 

[pkirkll]

Oh yeah, i jusr checked my 5 batteries and after running them for only about 2-2 1/2 miles the charge was averaging about 7.7v---balance was all good...

 

[dogman dan]

Goody. Sounds like you got it bolted up right, unlike my first try.

I'm a bit confused about the controller now. I've never seen one speced at an amps range. It's either 30 amps, 40 amps, etc. Not 30-100 amps. I'm completely clueless about what that means. Maybe it means they overstate it's rating to make it sell?

Could it be that you can get 100 amps very breifly for a good start up, then it ramps down to 30? Most controllers will do that, the typical 20 amp brushless controllers allow about 30 amps for a bit, then they ramp down to 22 amps max.

The only way to really know what your system is doing is to measure it with a wattmeter. There are inexpensive ones out there, ebay, hobby king, etc. But the gold standard for bikes is the cycleanalyst. The controller is speced for a 1000w motor, so it looks like the right one after all. Your motor can take about 1000w with no problems except for climbing a long long hill.

Your speed is spot on for 36v. You'd only see 30 mph if you rearrange your batteries to have 14s, 48v.

Once at speed on the flat ground, at 23 mph you will only be drawing about 800w, even with your weight. So you shouldn't overheat unless you ride up too steep hills. Normal street riding will work fine, just don't go hit the steep as hell streets or dirt trails with wicked grades. Don't climb hills the motor can't climb at least 15 mph.

You have 10 ah of 25c battery. So theoretically they can discharge 10x 25 amps. 250 amps. No problems with a too weak battery for you. 30 amps shouldn't faze em any.

Check those axle nuts. Don't let em get loose.

 

[pkirkll]

Thanks for everything all of you!

I let a guy at the shop ride it today and he came flying back around the block with a goofy grin on his face.... :lol:

 

[pkirkll]

Thanks for everything all of you!

I let a guy at the shop ride it today and he came flying back around the block with a goofy grin on his face.... :lol:

 

[dogman dan]

Nice! Maybe you've made a new ebike freindly local bike shop.