My first test with dewalt and 4110 fet upgrade

[Doctorbass]

Simply incredible!!!.... I repeat INCREDIBLE!!!

After waiting for long time about my fet order, i finally received these. I am very happy cause it's now time for high voltage fun! I waited 1 month to comeback with my 66 or 72V setup... i waited using only at 33V during the entire last month... :x

I installed these on my controller today.
-upgraded the + and - rail bus bar with 3x 12 gauge wire close to each phase fet group

- replaced the ramp capacitor to a 2.2uf instead of 10uf

-replaced the fix current limit R13 with a 10 turns pot to get variable current limit and allo the shunt to stay intact for my cycle analyst

-Decreased the LVC to 25V instead of 29V (when using with 1s 4p dewalt pack.

-changed the pos and neg power wires to 8 gauge

-re positioned my battery pack holder in the triangle instead of the rear rack... my bike is alot mure stable and weight balanced!


-AND I finally TESTED!!

First i was nervous about powering it and risk of blowing my new fets.... but i was lucky... I double checked each solder, pcb traces, polarity.. etc

I installed my DC clamp meter with peak hold on one of the battery pack wire (tested at 2s2p pack =67.7V standby)

I started by puting the pot to 1 turn out of 10. and put the throttle to the max quickly. I recorded 9.9A

i increased it to 2 turn.. I recorded 14A and observed that the acceleration increased significantly...

..... 3 turn...

...

7 turn and reached 48A... WOWW !!!! Too much torque!!! I simply do a wheelie when i put the throttle to the max!!!... I need to go to the front of the bike to keep the front weel on ground!!!!

that's 2640W at 55V ((due to the A123 cells at 10C) 2.8Vx10cells x 2s=56V)

Oupss... I remembered that i also installed a 40A fuse inside the controller to protect it... maybe i should be carefull with this pot...! :wink:

maybe also i will install a torque arm.. I know.. I know... .... for sure i will!!

I just can't imagine if i increase it again... again to 8 or 9 turn..!!! the R13 for current limit goes to around 310ohm if I remember...

I climbed a long hill near my house and I got 42kph !!!.. I when i come back i got 67kph on return... and 52 on flat... (i'm at 66V ) I got also 57 on my old 72V SLA..)

I will get my new GPS and will post the slope value of it soon.


I also have 3 more dewalt pack to install (the one i got for free..)



I am simply amazed!! happy !... and proud of that installation!


Doc

 

[Lowell]

"7 turn and reached 48A... WOWW !!!! Too much torque!!! I simply do a wheelie when i put the throttle to the max!!!... I need to go to the front of the bike to keep the front weel on ground!!!!"

You'll get used to it. That's like... every time I ride my bike :lol:

Do you think there's a market for a ready to run, hot rodded controller? If you had to do another one, how many hourse labor do you think it would take?

 

[Jozzer]

hehe, your having fun!
did you notice what the voltage sag was like at 5C? And at 2C? (or were you too impatient to turn it up higher and didn't notice :wink: )

 

[safe]

...that's 2640W

So do you consider such a machine a "bicycle" or a "small motorcycle"?

(that's 3.5 times over the legal limit in the US and 10.5 times Europe)

I'm fearful that once people realize how easy it is to increase power that we're going to see people getting hurt and laws clamping down on what we do.

BE CAREFUL!!!

That sounds like awesome power on a bike.

Lowell owns a road racer type motorcycle (a FZ600 I think) and knows how to ride, but do you have a background in fast bikes? Are you wearing protective gear? I ride with a helmet, knee pads, elbow pads, gloves and if it's cool enough leather, otherwise (like this time of year) I don't.

LiFePO4 is going to open the door to cheap batteries that don't have much range, but their discharge rates are so impressive that people will be able to pump out huge power for short bursts. In some ways the old Li ion batteries with their 1C limitations sort of put a limit on peak power.

LiFePO4 is going to change things....

 

[fechter]

Doc's got the combination of torque and speed that I would be real happy with. I don't need to go super fast, but I have serious hills.
Pulling wheelies can be fun too.

Just because you have a lot of power doesn't mean you always have to use it. Headroom is good.

 

[Doctorbass]

Thanks again for your care and advice about me guys! :wink: I like fast ride, but only 10% of time i think .. and it's late on the night on some industrial park road.... I prefer to climb hill and burn some tire!... . The mean speed of around 45kph is of for me too. I would try if the 5304 is lower in torque than my 5305...


I consider seriously to put some torque arm soon!

After changing the 10uF caps for the rampto a 2.2uF, the acceleration increased alot more! and with the wheel on no load, it hit the full speed in less than 1/4 of sec!!

I just can't imagine the torque on the axel!!

Doc

 

[xyster]

After changing the 10uF caps for the rampto a 2.2uF, the acceleration increased alot more! and with the wheel on no load, it hit the full speed in less than 1/4 of sec!!

I just can't imagine the torque on the axel!!

Doc

The effect of changing the ramp-up capacitor value is really good to know. To save my dropouts, I wasn't planning on changing the ramp capacitor like you did. I don't think Lowell changed his ramp cap either, but he can still pop wheelies with his 5304/20" and 100 amp controller.

 

[Lowell]

I'm going to try the lower value capacitor soon

 

[xyster]

I'm going to try the lower value capacitor soon

Figures... But what's the point? Is a faster ramp going to increase your bike's acceleration? Seems your problem now is traction, and keeping the front end on the ground.

 

[Jozzer]

Hehe, come on Xyster, you know he wont be happy till his bike takes off on one wheel and dumps him in a bush!
Now, where to get caps in the UK

 

[numberonekiwi]

Hehe, come on Xyster, you know he wont be happy till his bike takes off on one wheel and dumps him in a bush!
Now, where to get caps in the UK

Try maplin

 

[Jozzer]

 

[Doctorbass]

2.2uf or maybe 3.3uF are some of the most s popular and you can find some in every cheap electronic gadget or radio or any stuff that use voltage higher than 9V. the caps rated 16V should be of but 25V rated are best for that controller application. you can dissasemble any electronic stuff that use DC circuit to find some... don't border you to search store to buy some!

Also I confirm a second time! The acceleration change if you replace this caps!.. but your acceleration depend on two thing I think: the current limit and the caps value for a x voltage.

Doc

 

[xyster]

7 turn and reached 48A... WOWW !!!! Too much torque!!! I simply do a wheelie when i put the throttle to the max!!!... I need to go to the front of the bike to keep the front weel on ground!!!!

that's 2640W at 55V ((due to the A123 cells at 10C) 2.8Vx10cells x 2s=56V)

Well it's nice to know I have wheelie-poppin' power already. Though my personal FET-ish isn't wheelies, but climbing steep hills. Too bad there's no quick-change capacitor for that! Guess I have to go the long route and replace my FETs.
Speaking of, I noticed Digikey has the IRFB4110s in stock again:
http://www.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=IRFB4110PBF-ND

 

[fechter]

Speaking of, I noticed Digikey has the IRFB4110s in stock again:
http://www.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=IRFB4110PBF-ND

Bet it doesn't stay that way very long.

 

[The7]

2.2uf or maybe 3.3uF are some of the most s popular and you can find some in every cheap electronic gadget or radio or any stuff that use voltage higher than 9V. the caps rated 16V should be of but 25V rated are best for that controller application. you can dissasemble any electronic stuff that use DC circuit to find some... don't border you to search store to buy some!

Also I confirm a second time! The acceleration change if you replace this caps!.. but your acceleration depend on two thing I think: the current limit and the caps value for a x voltage.

Doc

Are you the only one who change the ramp (soft-start) capcitor from 10uF to 2.2uF ?

From KA3525 data
Using the formula t = CV/I
If V = 1.3V ; I = 51us.

Case 1
Uing stock 10uF
ramp time t = (10u*1.3 )/51u = 0.25 sec

Case 2
Using 2.2uF
ramp time t = (2.2u*1.3)/51u = 0.056 sec

Comment:
The current will ramp up to its current limit in less than 0.06 sec for case 2.
Thus it will reduce the response time by 0.2 sec.
Theere should be no problem to the motor and the controller because they are current limited.

Now which case would you or others prefer? Why?

 

[Doctorbass]

Case 2 for sure!

In theory, that seems to be not signifiant difference in the results of the acceleration .

But! i really tested it and the feeling is totally amazing!

for exemple, with the stok 10uF, if i put the throttle to the max while the weel is free, it accelerate and get the max speed in around 1sec

Using the 2.2uF, the weel get instantanously the max speed.. like if it have no acceleration time... like DIRECT... I hit the max current in same time too.

When i'm in the bike, the accelecation is quite faster!.

I will post a video of that soon.

 

[The7]

I am still using the 10uF. It seems that there is some feeling of "Turbo Lag" in an turbo-charged gas engine.

My ebike has an geared hub with freewheel.
When cruising with throttle-OFF, the motor will stop due to internal freewheel and the ebike continues to coasting.
When I turn ON partially to regain speed, there is an significant "LAG". The motor seems to need some time to ramp up to speed in order to engage the drive wheel. During this LAG, there is some initial drag feeling and there is overshoot feeling after this LAG.
This LAG also happens in starting from dead stop.

Wonderng whether this LAG is due to an excessive ramp time (0.25sec)?
Would 2.2uF help to reduce this LAG?

Would this LAG also occur in non-freewheeling hubmotor?

 

[xyster]

I have a stock 35 amp controller. At 80 volts I don't notice any lag, but definitely notice the ramp, which seems a lot longer than 0.25 seconds. Are you sure, The7, that there isn't some additional mechanism or process going on that multiplies the ramp time? The ramp time feels closer to 2.5 seconds than 0.25 seconds.

 

[fechter]

I still have the original 10uf in mine, but the ramp up seems pretty instantaneous. Perhaps there's something else in the circuit that affects the ramp up speed. It seems like there's quite a bit of variation between individual controllers.

I like the fast ramp-up. I can use my wrist to control it.

With a freewheel between the motor and the wheel, it takes some time for the motor to wind up to speed after coasting. I always found this to be annoying, along with the clunk you get when the freewheel grabs. I guess that's the trade-off for eliminating motor drag during coasting.

 

[The7]

I still have the original 10uf in mine, but the ramp up seems pretty instantaneous. Perhaps there's something else in the circuit that affects the ramp up speed. It seems like there's quite a bit of variation between individual controllers.
.

From the data:
the calculated "soft-start" time is typical 0.25s, but it could vary from 0.16s to 0.5s for different PWM chips using 10uF.

I would think 0.25s is a large LAG.

Would like to find is there any other ramp-up speed circuit?

 

[fechter]

I never fully traced out the part of the circuit between the throttle and the PWM chip. There are a couple of op-amps there that could also be limiting the ramp up.

 

[The7]

I have a stock 35 amp controller. At 80 volts I don't notice any lag, but definitely notice the ramp, which seems a lot longer than 0.25 seconds. Are you sure, The7, that there isn't some additional mechanism or process going on that multiplies the ramp time? The ramp time feels closer to 2.5 seconds than 0.25 seconds.

Did the 2.5s ramp time occur at no-load (with drive wheel off ground)?
Ramp up from what speed to what speed?

 

[xyster]

I have a stock 35 amp controller. At 80 volts I don't notice any lag, but definitely notice the ramp, which seems a lot longer than 0.25 seconds. Are you sure, The7, that there isn't some additional mechanism or process going on that multiplies the ramp time? The ramp time feels closer to 2.5 seconds than 0.25 seconds.

Did the 2.5s ramp time occur at no-load (with drive wheel off ground)?
Ramp up from what speed to what speed?

No, it's just my purely subjective assessment of the time it takes for the rush of power to build between about 0 and 5 mph. I could be mistaking normal, single-speed brushless motor operation for the current ramp. My 1500W brushed, single speed scooter feels about as quick between 0-5mph as my X5 ebike at 2800 watts -- and the voltage/speed of each is about the same (both go about 24mph at 48 volts), so the gearing is roughly the same. After 5mph, it's all ebike...

 

[TylerDurden]

Could a trimmer-pot be added ahead of the cap to make the ramp adjustable?