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A couple of questions on the controller 3-speed switch

alfantastic

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Info: 9 fet 30A Cellman Infineon, MAC 10T, Ping 48v 15Ah.

1) When limiting the speed via the 3-speed switch, does it act on the controller exactly the same as if you are riding on part throttle?
I.e. Does it only attenuate throttle signal, or is it a bit more technical than that?

The reason I ask this one, is due to reading that it's best to use WOT to help prevent overheating.
On a steep hill on the lowest speed switch setting, could this cause an overheating problem?
Hope you get what I mean :oops:

2) Can any damage be done to the controller or motor if the switch is flicked between modes, whilst on WOT?
I.e. If flicking from highest speed setting to lowest when on WOT.
 
I'm not sure about this and I did not try it myself, so take it for what it worth.

I think that the 3-speed switch is plugged in a different port of the controller with pre-programmed values.
It would be logical to think that those value are Low-33% Medium-66% and High 100% for most controller.
The % correspond to the % of throttle signal.

I do not see any problem switching from high to low.

Concerning the overheating, if a short/steep hill is present go WOT before the hill and keep it that way up.
If the hill is longer maybe medium/low with pedal would be better.

A simple way to check for overheating of the controller/battery/motor is to just touch them.
Motors can generally take a lot heat, but if the motor case is burning hot you have a problem else it should be OK.
 
vodk1c3 said:
I'm not sure about this and I did not try it myself, so take it for what it worth.

I think that the 3-speed switch is plugged in a different port of the controller with pre-programmed values.
It would be logical to think that those value are Low-33% Medium-66% and High 100% for most controller.
The % correspond to the % of throttle signal.

I do not see any problem switching from high to low.

Concerning the overheating, if a short/steep hill is present go WOT before the hill and keep it that way up.
If the hill is longer maybe medium/low with pedal would be better.

A simple way to check for overheating of the controller/battery/motor is to just touch them.
Motors can generally take a lot heat, but if the motor case is burning hot you have a problem else it should be OK.

Thank you for your answer vodk1c3.
I don't personally get any overheating issues, as I WOT on hills anyway.
I just wondered that if the speed switch attenuates the actual throttle signal, then riding a steep hill at the low setting would be the same as riding that same hill part throttle. This could create a heat issue??
I'm just guessing at this theory. Can anyone shed some light on this please. The more technical the better :D
 
I think you have that right about the throttle signal.

The advantage of the switch is when you want to have more controll over the throttle setting in a low speed, crowded type place. Or you want to hold the throttle WOT for comfort, but have a lower top speed for economy.

But I could be wrong about how that specific controller acts. What I have seen with other controller three speed, and other controller speed limit jumpers is that you still get full wattage under load breifly when you leave a stop sign, but then you reach a top limit. At that point the controller is likely to be still pwm ing if maxed out on the slow setting. But again, I don't know for sure. I have always assumed it is pwming at all times on the low setting.

So a long hard hill might result in a hot controller. I say might, because you can lessen the load on the motor if you pedal your guts out. That's how you get up a hill cooler if not able to blast it. Half throttle, and keep it moving fast enough by pedaling your guts out. Riding with a temp guage proves this works for the motor. But the controller may get warmer. Just depends on how much power half throttle still is. A 20 amp controller won't overheat.

I've been intrigued by the idea of a switch that engages extra shunts. So you'd still have full voltage speed in all settings, but you could choose amps settings with a flick of a switch. Say 20-30-40 amps? Even if the switch had to be located on the controller, it would be nice.
 
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