Do you think this 72v controller can handle 84v?

[wesnewell]

Images in listing aren't working now, so couldn't say. You don't have to connect the 3 speed switch if you don't want to. The speed sensor wire is for a speedometer hookup. I don't use that type and know nothing about them. If you have a built in speedo that a wire went to the controller, then hook it to that.

 

[LarryHoova]

Images in listing aren't working now, so couldn't say. You don't have to connect the 3 speed switch if you don't want to. The speed sensor wire is for a speedometer hookup. I don't use that type and know nothing about them. If you have a built in speedo that a wire went to the controller, then hook it to that.

Ok cool thanks. So is there a 3 speed switch wire(s) coming out of the controller that WAS connected to my 3 speed switch on my bike? And I simply don't connect anything to the controller or are you saying I need to disable the switch built into my bike?

I am pretty sure my speedometer was hooked up with a single wire so that should match.

 

[wesnewell]

the factory controller on you bike was designed for it. I have no idea what they did a I don't have one. Many things are fairly generic for most controllers, but when replacing the controller, you'll have to figure out how the original was wired and then adapt the new controller to it. Since I have neither of the controllers, I'm giving you an educated guess as best I can based on how most controllers function. A brushless motor with halls will always have 3 phase wires and 5 hall wires, but that's where the similarities end. I had to figure out which wire went where when I changed controllers and they didn't hook up the same way as the original. IOW's, you're going to have to experiment a little from a base starting point unless you can find someone that had your controller, and replaced it with the controller model you buy and can remember exactly which wire went where.

 

[LarryHoova]

the factory controller on you bike was designed for it. I have no idea what they did a I don't have one. Many things are fairly generic for most controllers, but when replacing the controller, you'll have to figure out how the original was wired and then adapt the new controller to it. Since I have neither of the controllers, I'm giving you an educated guess as best I can based on how most controllers function. A brushless motor with halls will always have 3 phase wires and 5 hall wires, but that's where the similarities end. I had to figure out which wire went where when I changed controllers and they didn't hook up the same way as the original. IOW's, you're going to have to experiment a little from a base starting point unless you can find someone that had your controller, and replaced it with the controller model you buy and can remember exactly which wire went where.

Ok got it thanks.

I have a questions. Before I could go 45km/h going uphill. How fast do you think I could go on flat or downhill without the limitation?

 

[wesnewell]

If you give me the specs on your motor and wheel size, I could give you a pretty close guess. What size wheel? Motor rpm@what voltage? Without some info a guess could be way off. All I can tell you is that it will be faster than before. Possibly as fast as 70kph using your 84V battery pack on level ground.

 

[LarryHoova]

If you give me the specs on your motor and wheel size, I could give you a pretty close guess. What size wheel? Motor rpm@what voltage? Without some info a guess could be way off. All I can tell you is that it will be faster than before. Possibly as fast as 70kph using your 84V battery pack on level ground.

It is a 500w motor. The wheel size is 17". I have no idea the motor rpm. At 60v it went 32km/hr, at 72v in went 39, and at 84v it went 46km/hr (because of the limiter in the old controller)

I keep checking the mailbox. Controller should be here any day now. I am really curious how fast I will go and how much torque it will have without doing a shunt.

 

[wesnewell]

What's the diameter of the wheel including the tire? I hope it's a lot more than 17". But even with that, not know the motor rpm, it's impossible to say with any accuracy.

 

[LarryHoova]

What's the diameter of the wheel including the tire? I hope it's a lot more than 17". But even with that, not know the motor rpm, it's impossible to say with any accuracy.

i think the rim is 17" - so I am about 22" with the tire on. It is a scooter style bike that is why the wheels are small.

How can I figure out the rpm of the motor?

 

[Ykick]

60v it went 32km/hr using 22" diameter tire (69.11" circumference) me thinks that's about 305RPM motor.

 

[wesnewell]

It won't be any slower than the original controller and if it's anything close to the GM 500W motor it will do ~55kph on an 84V pack, but will overheat in 4.7 minutes at that speed. Slow down to 47kph and it won't overheat.

 

[LarryHoova]

It won't be any slower than the original controller and if it's anything close to the GM 500W motor it will do ~55kph on an 84V pack, but will overheat in 4.7 minutes at that speed. Slow down to 47kph and it won't overheat.

Cool. I can't imagine being WOT for 4.7 mins lol.

Considering it will be 45.5 going up a steep hill it should be able to hit 55 on flat, downhill - who knows

 

[rich43]

I run 100.8 volts through my 72v controller but that's right on the limit, definitely wouldn't push it any more.

 

[LarryHoova]

I run 100.8 volts through my 72v controller but that's right on the limit, definitely wouldn't push it any more.

That is the most I will be pushing. How fast do you go?

 

[LarryHoova]

controller finally arrived today!!!!!!!!!

Going to pick it up now - then solder this baby up - oh god I hope it ain't hard to do

I will post a speed test later tonight whoooooooooo

ironically I have to walk to the post office to pick it up.

 

[budafuko]

nope, fully charged is 103.6V

A fully charged 12V sla battery, depending on temp, is 13-14V max. Usual is ~13.5V @25C. I've never seen one above 14V, which would be 98V. I'm curious how you came up with that figure. Charge voltage for 7 batteries is series would only be 101.5V at recommended max charge voltage of 14.5V per battery. These aren't vented LA that you should equalize charge at 15.5V. And even at 14CV you will be doing nothing but burning them up faster. As soon as the charge is removed, they will drop under 14V each.

* Every chinese charger charge to 14.6-14.8V and do float to 13.6-13.8V (if have float)

fully charged floating charge with my chinese 48v charger is 59.2.. 59.2 devided by 4 is 14.8 .... 14.8 multiplied by 7 is 103.6 .. so a floating charge for a chinese 84v charger would be exactly what he said. although they do drop down to 14v when you pull them off the charger. and again to 13.25 if they have been off for a while

never leave your chinese battery charger alone. i have had several times where my batteries are unevenly discharged and i can not get them to charge higher than 58.9 .. i loved my old charger. floated at 58.8. always shut off

 

[ddupuis]

You want a 72V controller with 100V caps and fets, get this one at less than half the price.
http://www.ebay.com/itm/Electric-Bicycle-Brushless-Speed-Motor-Controller-72V-1500W-For-E-bike-Scooter-/360643164862

I ordered this controller a few days back for my scooter. hoping to run 84v. i fried my 48v controller @ 84v but not till after they were on the
charger. before charging the thing was crazy fast. something i would be very happy with. worth the 60 bucks to test it...

 

[wesnewell]

And your charger is prematurely killing your 4 batteries. A float charge should not exceed 13.6V for a 12V lead battery. That's 54.4V.
http://en.wikipedia.org/wiki/Float_voltage

 

[wesnewell]

If you run 84V lead on that controller, you need to have lvc changed from the default 62V to 72V or keep a close eye on voltage and stop to recharge when it gets down to 72V resting. Otherwise you'll kill your pack quite fast.