Quick CA question (throttle override override)

[bjosta]

I'm using the amp limit in the CA, works great.
Can I run a single toggle switch on the throttle wire from the CA to the controller to toggle the speed/amp limit feature on/off? Would there be any Ill effect of doing this?
I haven't checked but I guess the wire colors are documented in the manual?

 

[amberwolf]

I'm pretty sure you can do that. I'm trying to picture exactly what you're describing, and I think it would work fine, without problems, but I haven't done this myself yet.

(I intend to do something like it, so that I can have a 20MPH city streets speed limit on the CA, but a very-easy-to-trigger switch that bypasses this for whatever max speed I can get in case I need emergency power for an in-traffic maneuver to avoid an accident or stupid person. )

If you want to know for sure if there are any gotchas with it, just email info @ ebikes.ca and they'll answer you pretty quick, probably within a day.

 

[bjosta]

yeah, the intention is to put a amp and speed limit on the CA to conserve battery usage but if I feel like burning some watthours for fun I toggle a switch and get "unlimited" performance.
Just though of a complication though, if cutting the throttle override I'm guessing the LVC stops working also? That would be bad...

 

[Philistine]

Bjosta if you want it for an option between inefficient and fast VS slow and efficient, why not use the three speed switch option (presuming you have an infenion or similar that has the option of the three speed switch) - giving you three choices anywhere in the range of 30% to 120% of speed (programmed with the programming interface). What kind of controller do you have?

 

[dogman dan]

Three speed switches are great for when you want to hypermile, and with a flick of the thumb, you can blast a hill or a stretch of dangerous road.

 

[bjosta]

I'm using the 25a 6fet infineon from ebikes.ca now but building a new bike with a 9FET EB209 based infineon. It's this 9fet controller I want to limit.
Yeah that 3 speed setting sounds great, I'm guessing there are plenty of threads here on ES with info? Any tips on where to start reading?
Is that a speed limit or amp limit control?

 

[Ariane]

Bjosta,

the post you may be referencing is the one here and it really works like you describe it :

http://endless-sphere.com/forums/viewtopic.php?f=2&t=15528

The correct wiring diagram is at the end of the post :wink:

I hope its help, good day!
Black Arrow

 

[bjosta]

Thanks BlackArrow, will definitely look through that wiring diagram, but it does cut the throttle override and that will elave me without a LVC.
I'm trying to confirm that the infineon 3 speed setting is actually current limiting and not speed limiting, then it might be what I'm looking for.

 

[Arlo1]

the three speed switch on the infinieon is power and top speed limiting. So 50% setting on the switch is 50% power and 50% top speed.

 

[heathyoung]

I'm using the amp limit in the CA, works great.
Can I run a single toggle switch on the throttle wire from the CA to the controller to toggle the speed/amp limit feature on/off? Would there be any Ill effect of doing this?
I haven't checked but I guess the wire colors are documented in the manual?

Yes, it will work BUT you lose all limiting - this includes LVC as well.

 

[jbond]

the three speed switch on the infinieon is power and top speed limiting. So 50% setting on the switch is 50% power and 50% top speed.

Don't think so. The three % settings for mode I,II,III only affect the max voltage and hence the max speed at you get with 100% throttle. It doesn't affect the current limiting and hence doesn't affect the amount of power available.

Re the question of current limiting with an over-ride. I picture a Pedelec control with an efficiency mode. Keep pedalling and get 50% of the normal current limit. But let the hand throttle over-ride this. So what we have is the PAS, CA and Throttle all feeding the throttle input on the controller. The CA pulls down the PAS voltage input to limit current. The hand throttle pulls up the other two to give you full speed/power. If I need fine control I just use the throttle. If I'm cruising, I use just the PAS with an efficiency current limit. If I need full power to climb a hill I use the throttle on max. I think this would be very intuitive to use.

I think this needs a couple of things to implement.
- A PAS that outputs 4.5v when pedalling
- A CA (obviously!)
- A couple of diodes or an op amp mixer to make the right signals take precedence.

 

[Arlo1]

the three speed switch on the infinieon is power and top speed limiting. So 50% setting on the switch is 50% power and 50% top speed.

Don't think so. The three % settings for mode I,II,III only affect the max voltage and hence the max speed at you get with 100% throttle. It doesn't affect the current limiting and hence doesn't affect the amount of power available.

Ummm Yeh it does I dont under stand why you are arguing this.
The 50% setting = 50% power (torque) and 50% top speed....
I Have an Infinieon and this is how it works.

Im my 18 fet 120% is my #2 setting the setting for when the switch is off. Giving me 85 km/h top speed and max torque
which injures most rookies when they try my bike.
#1 is 45% giving my slow acceleration and 46km/h top speed
#3 is 75% giving me moderate acceleration and 65 km/h top speed.

 

[jbond]

Don't think so. The three % settings for mode I,II,III only affect the max voltage and hence the max speed at you get with 100% throttle. It doesn't affect the current limiting and hence doesn't affect the amount of power available.

Ummm Yeh it does I dont under stand why you are arguing this.
The 50% setting = 50% power (torque) and 50% top speed....
I Have an Infinieon and this is how it works.

Im my 18 fet 120% is my #2 setting the setting for when the switch is off. Giving me 85 km/h top speed and max torque
which injures most rookies when they try my bike.
#1 is 45% giving my slow acceleration and 46km/h top speed
#3 is 75% giving me moderate acceleration and 65 km/h top speed.

Ok. That's not how I understood it. But hey. It's your controller. Here's what I'm thinking. Let's say you're in #1. You have a 30A current limit and a 48v battery. You're currently doing 35kmph. Open the throttle fully and you're going to go into current limiting. So now you have 30A and whatever voltage going to the motor that keeps the current below this, say 24v. Now switch to #2. Same speed. You're still limited to 30A. The motor voltage will be the same 24v. Power and torque available will be exactly the same. The difference is that as you get close to the #1 46kmph, the motor is hitting it's noload rpm for 24v. Power/torque drops off, the controller drops out of current limiting and you can't go any faster.

My bike has an LZDSZ controller that is very very similar to the typical Infineon. If I force it up a hill that means speed is below the Low mode limit and then switch to the High setting *nothing* happens. The controller is in current limiting in both cases. Which is why I think these modes effectively change the max voltage available to the motor and hence top speed before no-load rpm, but they don't affect power/torque across most of the speed range because that's limited by the battery and phase current limits.

 

[bjosta]

Im my 18 fet 120% is my #2 setting the setting for when the switch is off. Giving me 85 km/h top speed and max torque
which injures most rookies when they try my bike.
#1 is 45% giving my slow acceleration and 46km/h top speed
#3 is 75% giving me moderate acceleration and 65 km/h top speed.

What's your max amp usage during heavy load under the 45%, 75% and 120% modes? Going up a step hill for example.

 

[Arlo1]

330 amp peaks in 120%
150 peaks in 45%
250 peaks in 75%

 

[Arlo1]

Don't think so. The three % settings for mode I,II,III only affect the max voltage and hence the max speed at you get with 100% throttle. It doesn't affect the current limiting and hence doesn't affect the amount of power available.

Ummm Yeh it does I dont under stand why you are arguing this.
The 50% setting = 50% power (torque) and 50% top speed....
I Have an Infinieon and this is how it works.

Im my 18 fet 120% is my #2 setting the setting for when the switch is off. Giving me 85 km/h top speed and max torque
which injures most rookies when they try my bike.
#1 is 45% giving my slow acceleration and 46km/h top speed
#3 is 75% giving me moderate acceleration and 65 km/h top speed.

Ok. That's not how I understood it. But hey. It's your controller. Here's what I'm thinking. Let's say you're in #1. You have a 30A current limit and a 48v battery. You're currently doing 35kmph. Open the throttle fully and you're going to go into current limiting. So now you have 30A and whatever voltage going to the motor that keeps the current below this, say 24v. Now switch to #2. Same speed. You're still limited to 30A. The motor voltage will be the same 24v. Power and torque available will be exactly the same. The difference is that as you get close to the #1 46kmph, the motor is hitting it's noload rpm for 24v. Power/torque drops off, the controller drops out of current limiting and you can't go any faster.

My bike has an LZDSZ controller that is very very similar to the typical Infineon. If I force it up a hill that means speed is below the Low mode limit and then switch to the High setting *nothing* happens. The controller is in current limiting in both cases. Which is why I think these modes effectively change the max voltage available to the motor and hence top speed before no-load rpm, but they don't affect power/torque across most of the speed range because that's limited by the battery and phase current limits.

No 50% is amps and voltage. So say #2 was 100% and 30 amps which give you 50km top speed and number one is 50%. Number one will give you 25 km/h top speed and 15 amps. But it also cuts your throttle resalution in 1/2. So it makes it easier to ride.

This is all very crutial on my bike because its so powerfull in the top setting it made it easier to ride and all throttle settings in the lower power modes. Luke (liveforphysics) has use my bike if you dont belive me and watch the vids in my sig!

 

[bjosta]

Thanks Arlo1,

For my use I'd rather it only cut amps and not also voltage. I'll open up my controller and see if I can find the solder points to try it out anyway.

 

[Arlo1]

Thanks Arlo1,

For my use I'd rather it only cut amps and not also voltage. I'll open up my controller and see if I can find the solder points to try it out anyway.

If you are using a Cycle Analist you can use it to control the amps not ony can it do that but the CA can control thrust which is even smarter then amps! I will try to find you a link

 

[jbond]

Arlo1, This is the key post I was working from.
http://www.endless-sphere.com/forums/viewtopic.php?f=2&t=14807&start=15#p327917

3. The throttle voltage directly controls the PWM duty cycle, but can be modified by the current limit circuit. This means that the throttle can command, say 50% rpm, but the motor may be running under too much load to spin up to this speed. What happens is that the excessive power demand, from supply current sensing, is fed back and the controller cuts back the duty cycle to reduce the motor current demand.

4. The speed settings (used when programmed in switch mode) are nominal percentages of the maximum allowable duty cycle, so directly control the motor maximum no-load speed. For example, if programmed to 30%, 70% and 100% the controller will only allow the motor to run up to those speeds. In effect, it's a throttle limiter, but it does have the effect of expanding the throttle mechanical range. For example, with 30% selected the full throttle travel will give 0 to 30% motor rpm, rather than 0 to 100% rpm, which can give better low speed control if required.

I've never read anything on ES about these speed settings affecting the PhaseCurrent or RatedCurrent settings. This is why it seemed to me that if conditions meant the current limit was active and it resulted in a PWM of 25%, it didn't matter what speed limit mode you were in or what speed limit was set as long as it was above 25%.

You quote
330 amp peaks in 120%
150 peaks in 45%
250 peaks in 75%
So what rated-phase current limits have you got set?

The bit I'm interested in (and the OP I think) is the possibility of having a reduced current limit but without the speed limit. As a human cycling I'm effectively a constant power source for the bicycle. With the wind behind me or downhill I go faster, uphills I go slower. I want to add a constant power assist from the electrics but without the assist just dropping to zero when I go over the artificial speed limit. So it's like saying the no-load rpm is 30mph but only adding a max of 250w. It won't hold 28mph on it's own, but if I pedal hard down hill my power+250w is enough to get there. So I'm wondering if there's a way of tricking the Infineon controllers to make the 50% speed setting 50% of the current limit but not 50% of the max PWM duty cycle. The only way I can see to do this at the moment is to set the controller to 100%,100%,100%, the current limit to something suitable for the battery+controller+motor (say 25A) and then use a CA to force an effective current limit of 50% (12A, say). For this, low power, low assist, low weight approach I'd use a motor-battery combination that got the high no-load rpm either by running a 36v motor at 48v or lacing a 200" motor in a 700c rim. And then manipulate the current limit to get an economy mode with an occasional full power mode for hills. This is a very different user interface to your full-on, high power setup. If you've got 2-3Kw available you need a motorcycle style throttle to control it. Whereas the low power-low assist approach could be done with just the On-Off switch of a PAS.

 

[Arlo1]

Ok so mine is not your normal controler its a methods 18 fet kit i built. So for more info serch that other wise i will post a link later. I have a double shunt and the shunt resistance is less then 1/2 of the normal resistance and my phase current and battery current settings are at the highest but when you mod the shunt you trick the controler to run more power because it has no idea what you did.

As for what jeremy said in the post you quoted he is basicaly saying the same as me but in a harder to understand way.
As for just limiting current but not top speed and having it on a switch thats best done with the CA