Warning:Throttle on brake release

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Iccarus
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Warning:Throttle on brake release

There is an issue I have noticed on my electric scooter that never occures on gas cycles. Here's the senario. Your turning into a drivway or something.(In my case a narrow driveway with brick walls on each side!) You're braking through the turn and about half way through the turn you ease off the brakes, The bike suddenly lurches forward (toward brick wall) fast reactions and a hard squeeze on the brake handles saved disaster. I had inadvertantly rolled on a little throttle while squeezing the brake handles. When I released the handle... instant zoom,Scared the hell out of me. I've been riding since I was about 12 years old and worry about this happening to someone less experienced. Just make sure you have the throttle closed all the way when you're braking and it's no problem at all. I don't think it's a safety concern, just thought I would mention it.

Tis the season to be ridin - Bill

Sandra Harris
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Re: Warning:Throttle on brake release

I had a good learning experience with my Motorino XPv. The throttle is the right handle grip on my scooter. Only had it for a few days when my intention was to mount and maneuver the scooter back into it's parking stall. I didn't notice that the key was in the on position and grabbed the right handle bar (the throttle) and there was nothing I could do but watch in horror as my brand new scooter went for a ride without a rider! ;) No damage to the electrical but it landed on it's right hand side and smashed the foot board, side panel and turn signal. Duck tape worked well until the new parts arrived! LOL I've learned to not get off the scooter without taking the keys out of the ignition! :)
Sandra Harris

Mikie
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Re: Warning:Throttle on brake release

Hey Guys-- I had my mishap when I had my hand on the throttle and I was off the bike and pushing it backwards. As I was pushing it the bending of my wrist turned on throttle on and the bike took off. I paniced and tried to compensate but the bike ended up on its side and broke the throttle--which I taped together until I could get the new one. I now turn off the ignition before I go backwards! I believe this is something to be very concerned about. So lets spread the word....Mikie

mikie

Iccarus
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Re: Warning:Throttle on brake release

Yes , it say's in the manuel to turn off the key when you stop the bike... now we all know why! The other thing that can happen is someone else twists your grip while you're on the bike and off you go! We're all so used to hearing the motor running that they will just assume it's off. The other big thing is in parking lots people don't hear you. Be carefull. I have to admit though, I do get a little sick pleasure seeing the startled looks on peoples faces when you ride up and surprise them. heh heh

PS Mikie, bummer about your bike, I've been hoping for good news. Kelly controllers is about 10 mi. from my house. I had heard good things about kelly controllers. I really want to get regen. I think those who say it's hardly worth it miss the point... why not? I want to hear what your bike will do with the gear you got. You could go with 28 or even 32 cells would fit easy. Also like to hear more about that 6kw hub motor.

2008 XM3500li Mods/Kelly KBL12251/84v 28cell 40AH pack/ Variable regen brake trigger on left brake handle/Givi/Cycle Analyst/Homemade BMS

KMX Typhoon Home build (recumbent pedelec) with two Astro Brushless 3220motors/twin castle Phoenix ICEHV 160/ Cycl

garygid
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Re: Warning:Throttle on brake release

Icc...,
I had the turn in the driveway (short, but an upgrade), gave a little throttle to my 5000li, that was too much, I gave a touch of brakes to slow, but then got an unplanned, sudden spurt forward, and I made a panic stop, resulting in the 350-lb "scoot" tipped too far over for me to keep it up, and then me wedged beteen the bike and the car!

Fortunately, some ice on a swollen spot on my leg should make things OK, ... but I was lucky.

Another CAUTION:
Trying to get going on a hill after stopping ... it is not easy to do.
Suggestions, Please?

Cheers, Gary
XM-5000Li, wired for cell voltage measuring and logging.

garygid
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Re: Warning:Throttle on brake release

With the 3500's 3-phase (or the 5000's 6-phase) motor, the Hall-Effect sensors normally provide phase timing information to the controller, right?

When starting from stopped, how does the controller know what to do?

When trying to start on a hill, and the motor is actually turning (slowly) in reverse, do the Hall sensors give misleading information?
Or, is the controller smart enough to do the "right" thing to get the motor going forward?

What happens as the motor speed nears zero under heavy load?

Cheers, Gary
XM-5000Li, wired for cell voltage measuring and logging.

MiniVan
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Re: Warning:Throttle on brake release

The direction of the motor is determined by the order the poles are energised. If the load on the motor is stronger than the force to move the stator from the current energised pole to the next, the motor stalls and you get the 'vibration' effect. This is why this style of motor hass less torque the higher the speeds as there is less time to energise the pole, hence less time for the magnetic field to act on the stator to turn the motor. Torque drops of at high RPM.

The controller energising the poles makes the motor go in the right direction.

I'm not sure of which hall-effect (magnet sensors) you mention. The one for the re-gen brakes?

A more on-topic reply, is that i rode my BionX bike for the first time today, and fell of my bike for the first time in years, trying to bump up on a curb, you lift the front wheel and then when it comes down, the pressure of the peddle can cause a surge (peddling controls the speed) and hey presto i was on the floor and me and the freshly painted bike all scratched up!

Iccarus
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Re: Warning:Throttle on brake release

I'm going to have to try a few steep hills first to see what you mean, but right away I would say the big problem is you can't just put it in low because they buried the high low speed switch. You need that eco switch where it is on the 3500. That right there makes it alot easier. Also I have further confirmed that doing that solder wicking mod on the controller made the throttle smoother on takeoff. The other 3500 I have is kind of touchy in high spead mode from a stop.(it doesn't have the mod the other does) When you get real good you will forget it was ever a problem. A funny thing happened today. I was on my scooter at a light and a guy asked me, "Where did you get that?" I said on the internet and he asked if I was on v is for voltage...ha talk about a small world! I said yeah I'm iccarus and we had to go. Kids love these e-bikes They're smarter than most adults I think sometimes. Sorry I really didn't anwer any of your questions but on the technical ones at least I'm clueless... I assure you. I'll see on the technique.

Happy riding Bill
28 cell 3500li-2006 prius

2008 XM3500li Mods/Kelly KBL12251/84v 28cell 40AH pack/ Variable regen brake trigger on left brake handle/Givi/Cycle Analyst/Homemade BMS

KMX Typhoon Home build (recumbent pedelec) with two Astro Brushless 3220motors/twin castle Phoenix ICEHV 160/ Cycl

antiscab
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Re: Warning:Throttle on brake release

This is why this style of motor has less torque the higher the speeds as there is less time to energise the pole, hence less time for the magnetic field to act on the stator to turn the motor. Torque drops of at high RPM.

The controller energising the poles makes the motor go in the right direction.

I'm not sure of which hall-effect (magnet sensors) you mention. The one for the re-gen brakes?

Not quite correct.
permanent magnet 3-phase sychronous motors are the 2nd highest torque dense motor there is (the first is the powered magnet 3-phase sychronous motor).

the reason you have torque drop off at higher speeds is because the back emf of the motor gets closer to the pack voltage:
motor voltage = motor current * internal resistance + constant * rpm

the max voltage you can apply to the motor is limited by pack voltage.
when the constant * rpm component is significant enough to force motor current to fall, torque drops off:
Torque = constant * motor current.

If you have a sufficiently high pack voltage, you wont ever experience torque drop off.

the above is a bit simplified (i treated the motor as a DC motor, rather than a 3-phase), but the concept is correct

the hall sensors report motor position at all times.
at all times, at least one of the sensors is high and at least one is low.
during transition, 2 of the 3 sensors are high, and the third low.

If a hall fails, then either the controller wont power the motor at all, or it will attempt to guess motor position.

Matt

Daily Ride:
2007 Vectrix, modified with 42 x Thundersky 60Ah in July 2010. Done 194'000km

garygid
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Re: Warning:Throttle on brake release

It appears that the "Econ Mode" switch on the 5000li primarily tells the controller to cut the max current to 50 amps (down from 100 amps). There is no mention of it in the manual.

The 4000's manual shows a Speed Switch" but says nothing about it.

The 3100's manual contains a STRONG warning to not change the switch setting while the bike is moving.

Since that switch on the 5000 is "hidden" in a locked compartment, one might assume that the same caution applies to the 5000li. I will try to get some more info from the "factory".

However, is it possible that the Econ mode puts the controller into a special "low-speed, high-torque" mode of driving the 6-phase motor?
I doubt it, since that would be such a great "low-gear" feature that it would at least be mentioned, right?

So, do you have any real reason to suspect that using the "Econ" mode would help me get up a steep hill?
Thanks

Cheers, Gary
XM-5000Li, wired for cell voltage measuring and logging.

Iccarus
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Re: Warning:Throttle on brake release

So, do you have any real reason to suspect that using the "Econ" mode would help me get up a steep hill?
Thanks

NO I just meant it makes starting without a sudden lurch easier. It sounds like lenny has the right idea on the other thread, just have some throttle on when you release the brake. I havn't had any problem but I've been riding a long time. I do see what you mean though. I wonder what the controllers cost for the 5000 because that shunt mod did seem to make the thottle control smoother on my 3500. You could take a chance and try it. I would like to know for sure about why they say not to use the eco switch while moving. I do it all the time with no problems. It's a matter of preference I guess, some people say they never use it.

2008 XM3500li Mods/Kelly KBL12251/84v 28cell 40AH pack/ Variable regen brake trigger on left brake handle/Givi/Cycle Analyst/Homemade BMS

KMX Typhoon Home build (recumbent pedelec) with two Astro Brushless 3220motors/twin castle Phoenix ICEHV 160/ Cycl

Mikie
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Re: Warning:Throttle on brake release

Yes it is a big bummer, It cost me $2000 for all of that mod work and then the motor(add another $600 for motor) comes up toast. I would love to be able to put 28-30 batteries in (once we get the 6k motor figures out) but seems like the hold up is a cheap charger that will do that many cells, why has no one used a zivan charger? seems like it would allow us to have much more flexibility in what packs we would like to assemble and then upgrade to?

http://www.electricmotorsport.com/store/ems_ev_parts_chargers_zivan.php

meanwhile I asked the tech, if possible to put the 3500 motor back on until we get the 6k figured out, that way at least I can ride! Mikie

mikie

Iccarus
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Re: Warning:Throttle on brake release

Mikie, The zivan is a 10amp charger to 96v right. I think the TSL72-15 is a better deal it's 15 amps charges 24 cells 87v in 2.67 hrs. I think it's a couple hundred dollars cheaper too. Then use one or two of the 10amp 4cell chargers I posted a link to somewhere else. They're $34.00 each. Thats what I'm doing with all the stock stuff. It would probably be better to just stop at 24 cells if 48mph is fast enough for a persons needs. It makes it alot simpler. Yeah I would go back to the stock package you'll probably be fine if you don't get to crazy:) I still want to try one though. were you going to have regen? That's what I want to do. I think about it every time I hit the brakes! GIVE ME REGEN OR GIVE ME DEATH!! Not having regen will quickly become primative.

2008 XM3500li Mods/Kelly KBL12251/84v 28cell 40AH pack/ Variable regen brake trigger on left brake handle/Givi/Cycle Analyst/Homemade BMS

KMX Typhoon Home build (recumbent pedelec) with two Astro Brushless 3220motors/twin castle Phoenix ICEHV 160/ Cycl

antiscab
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Re: Warning:Throttle on brake release

regen could be a bit tricky.

the only way i could get regen to work safely on my emax with the kelly 400A controller was to use the first bit of throttle travel. so at 0 throttle, regen is at what i set it to (which is the most braking effect you want on your back wheel in the dry in an emergency stop).

more throttle reduces regen until power becomes positive again.
i couldnt get the regen on brake signal low enough (read dangerously strong even in the dry) and hooking up the second throttle for regen made no difference.

anyway, regen on my setup increased range by a mere 1%.
once in a blue moon i go to a friends house who lives on top of a very large steep hill.
coasting down i get up to 80kmh (50mph), so i need to brake to keep speeds vaguely safe.
this is the only time i get 2% more range.

each time i come down from 42mph (70kmh) i recover about 0.1AH (my pack voltage under regen is 63.x v)
peak current is around 25A, and falls away as i lose speed.

increasing regen power wont get me more recoverable energy on my commute (i did try though :) ) but does stop me faster (rear biased braking, back wheel skids under emergency brake).

Matt

Daily Ride:
2007 Vectrix, modified with 42 x Thundersky 60Ah in July 2010. Done 194'000km

Iccarus
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Re: Warning:Throttle on brake release

Yeah, I guess variable regen is easier with a/c motors. At least thats what i've heard. Your system sounds good, once you get used to it. using regen braking in E-bycycle tests have shown between 7% to 12% depending on the type of riding. I like you're idea of hooking it direct to the throttle. I try to coast up to lights anyway. (the most efficient way of converting inertia right) Do you do a lot of city driving, thats where you get the big returns. Anyway 1% is still better than 0% so the quest continues. Remember the 3500li said it was regen "capable" has anyone tried it with the stock XM equipment?

2008 XM3500li Mods/Kelly KBL12251/84v 28cell 40AH pack/ Variable regen brake trigger on left brake handle/Givi/Cycle Analyst/Homemade BMS

KMX Typhoon Home build (recumbent pedelec) with two Astro Brushless 3220motors/twin castle Phoenix ICEHV 160/ Cycl

antiscab
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Re: Warning:Throttle on brake release

actually, the emax setup is AC, as are all the extreme scooters, and just about any scooter made since 2005.
the problems ive encountered have mainly been with how the software is setup on the controller (the sort of thing an update could fix later on).

in theory, the kelly actually accepts dual throttle input.
one for forward torque
one for backwards torque
normally only the forward accelerator is active.
if you are moving forward and the brake switch is on, the backwards accelerator becomes active. however, even at 0, the minimum regen was much to powerful.
if you are stationary or moving backwards, and the reverse switch is on, the motor will operate in reverse.

even though the regen doesnt quite work, im very impressed with it.

i do on occasion do some stop-start riding in peak hour traffic.
on this occasion, the return for me is around 3.5%
still not worth changing controllers for, but it you have to anyway, you may aswell.

Matt

Daily Ride:
2007 Vectrix, modified with 42 x Thundersky 60Ah in July 2010. Done 194'000km

Iccarus
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Re: Warning:Throttle on brake release

Thanks Matt, Thats what I'll do wait till I need a new one or start a project. What I was hoping for is a way to do it with the stock stuff.

2008 XM3500li Mods/Kelly KBL12251/84v 28cell 40AH pack/ Variable regen brake trigger on left brake handle/Givi/Cycle Analyst/Homemade BMS

KMX Typhoon Home build (recumbent pedelec) with two Astro Brushless 3220motors/twin castle Phoenix ICEHV 160/ Cycl

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