Complete Newb

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DUIguy
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Complete Newb

Well after plugging around the site for a bit, I figure I better jump in. I'm not new to the forum concept, just the entire world of EV's and even the terminology / concepts of electric motors is all. :) So back in Physics 101, I remember the terms volts, amperes, resistores and such, but I didn't do well in that part of the class, yet I majored in Chemistry. I appologize in advance for my ignorance, and hope not to offend. I'm not an idiot, per se, so hopefully I'll catch on soon.
I've joined the ranks of small EV owners and purchased a BladeZ 450 XTR-S Transport. I've owned it for 3 days. Now I'm trying to understand it so I can make it faster.
This is what I know. It's a 24V vehicle, powered by to 12V, 12Ah (don't understand that yet) batteries wired in paralell (or series, i don't remember what that is either). I've read of the ability to add a third battery without too much modification (i.e. buying a new controller, throttle, motor, etc.).
I've spent my money so far, and I am not looking to gut it and spend 300-500 to get 5mph more. I'm looking for the "no-brainer" (emphasis) upgrades or mods that are the cheap and dirty ways to get 5mph more out of it.
I've fried my eyes, staring at the screen, following links of promise of 1000W motors with 48v and wheelies, and realized that I am still in the shallow end of the pool.
Oh, and I'm am fat at 238lbs and 5'10". :) So messing with the gears isn't too much of an option, cause torque is too precious.
So besides being told what to do, I'll take suggestions on readings as well. I'd like to learn more about the watt/ amp/ volt/ Hp/ relationship without enrolling in a class and without picking up a book weighing more than my scooter. Any electronics for dummies sites out there?

Thanks in advance,
Grant

p.s. I noticed some "last" posts are a little old. Does this board still get good traffic?

LinkOfHyrule
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Re: Complete Newb

Can't say that I've owned that scooter, but adding another battery is about the most straightforward mod you can do. The biggest challenge is almost always where to place it if there isn't more room in the battery box.

The batteries currently in the BladeZ are in series (series adds up the volts, parallel adds up the Ah [amp-hours]). Assuming the controller can take it, it's as simple as putting a third 12V 12Ah battery in series with the existing ones. You'll need a new charger, remember. 36V 1/1.5A chargers can be had for like $25. A 12V 12Ah SLA battery will probably run you between $35 and $50 depending on source and pedigree.

Mind whatever low voltage cutout protection was in place won't work with the extra battery, so take heed not to drain the batteries too badly. SLAs (the type of battery in your scooter) don't like it when they're run down very far.

Check out the basics section for some reading. It's fairly comprehensive.

This board gets decent traffic. Not as much as the Endless-Sphere forums (which are more centered around ebikes), but it's fairly prestigious.

The author of this post isn't responsible for any injury, disability or dismemberment, death, financial loss, illness, addiction, hereditary disease, or any other undesirable consequence or general misfortune resulting from use of the "information" contai

andrew
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Re: Complete Newb

Here are some links to resources. I should probably make a FAQ for electricity and motor basics.

A very basic explanation is:

Amps: flow of charge that makes a motor produce torque.

Volts: Energy per unit of charge. Determines what speed a motor produces torque.

Watt: Unit of power. Determined by multiplying amps * volts, or by multiplying torque * speed

Hp: Horsepower. Just another measure of power equal to about 745.7 watts.

Increasing the voltage makes a motor produce the same amount of torque at higher speed, or produce more torque at the same speed because the motor will draw more current. In practice, what this means is without changing the way the motor is geared to the wheel, it will produce both more torque and speed at a higher voltage, or draw more current at a higher voltage. As you can see, this is more power both as input, and output.

The risk is causing the motor to heat up too much. Current flow (amps) causes wires to heat up due to resistance. And, as stated, without changing the gearing, increasing the voltage will cause more current flow. In fact, this is the goal so that the motor will produce more torque to speed up faster. So, it is a real good idea to determine about how hot the motor is getting now. If it is not getting very hot after a long ride, then it may take more current safely and an overvoltage mod may work.

Another risk is frying the controller. The semiconductors within the controller that switch on and off real fast to vary the flow of electricity are rated for a certain voltage, and tend to not be very forgiving if this voltage is exceeded. A less significant risk (but still important) is sending too much current through the controller will cause more heating. Generally controllers have over current and/or overheat protection, but some don't. It is a good idea to determine how hot the controller is getting now after a ride.

Due to the risks involved, I would go with a 6v increase provided the motor or controller is not getting very hot now. This would be much more mild on the controller and motor. 12v increase is a big margin on a 24v system (50%). Keep in mind a lot of people moding here don't care so much about longevity, just about getting more speed out of a scooter instead of upgrading (or buying something more expensive). This is a gamble. It's exactly like the logic in overclocking a computer. If it's old and can't really be sold for much then who cares if you fry it for a chance to get more performance? That of course means it doesn't make sense at all to overclock a new computer in the same way. If you have a new computer, then you probably want to be more careful and settle for a mild overclock to get some life out of it.

Really what you are doing is using what information you have to safely take advantage of the tolerance engineered into the product. Every product manufactured for any purpose has a certain amount of extra tolerance built in for quality and to ensure operation without failing. Sometimes this can be exploited with very low risk if you have the necessary information that the manufacturer couldn't account for. Like, they had to plan for the motor hauling maximum weight up the steepest grade in the hottest weather, and still remain within safe operating temperature (which itself has some tolerance).

Anyway sorry to ramble on. Last, I would recommend using a 6v charger, and not upgrading the string charger. The more batteries you charge in a string without any form of balancing or charge regulation, the more risk there is of damage. batteryspace.com sells some 6v chargers, and 6v batteries can be gotten from most battery manufacturers.

[url=/forum-topic/motorcycles-and-large-scooters/587-my-kz750-electric-motorcycle-project]KZ750 Motorcycle Conversion[/url]
[url=/forum-topic/motorcycles-and-large-scooters/588-fixing-my-chinese-scooter]900 watt scooter[/url]
Pic from http://www.electri

DUIguy
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Re: Complete Newb

Sounds like good advice. A 50% increase is a big jump. Would that be a 6V 12Ah battery? Do the amps have to (should) match? I can make-shift a spot for the battery in a couple of locations, then I'll wire it to the other batteries. There is a fuse between the two current (no pun) batteries. I think it was a 30A. Would you suggest the same between the the add-on battery?
As for recharching it, there will be three batteries in series. I'll be using one charger for the 6v and another for the remaining 24v. So, I'll have to disconnect the third battery at the terminals and have a jumper wire to complete the circut for the 24v side, right? I don't want to fry anything.
I've done a large portion of your suggested reading, thank you. Much more to learn though.
Grant

andrew
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Re: Complete Newb

The ah capacity of the add-on battery should match the existing batteries. It also would be okay to get a higher capacity battery if you can't find the exact same, but not lower.

It wouldn't hurt to put another fuse in the circuit between the add-on battery and the rest of the pack. This would be a good safety feature, especially if the add-on battery is mounted in another location from the others. Put the fuse as close to the add-on battery terminal as possible.

You wouldn't need to disconnect the batteries during charging. They can all remain in series, just make sure and tap off the two original batteries for the 24v charger directly, and run the 6v charger wires to the 6v battery. The controller may have a charger input connector now. You would be bypassing this, and sending the charger wires directly to the batteries. It is best for the charger wires to be fused, so make sure and wire the 6v battery charger wires so the added fuse is in the circuit. With the original fuse wired between the existing two batteries, then it should be in the circuit for the 24v charger wiring.

If you want to go extra safe, then you could put two low-amp rated fuses (rated slightly above the max charger current) in the charger circuits as close to the battery terminals as possible.

BTW, if you are looking for a smart 6v charger, I noticed batteryspace.com carries one.

[url=/forum-topic/motorcycles-and-large-scooters/587-my-kz750-electric-motorcycle-project]KZ750 Motorcycle Conversion[/url]
[url=/forum-topic/motorcycles-and-large-scooters/588-fixing-my-chinese-scooter]900 watt scooter[/url]
Pic from http://www.electri

andrew
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Re: Complete Newb

BTW in this thread:
blade-z 450w motor extra range v. extra speed you may notice that I recommended the 36v mod for the Blade Z 450w because it was working for anydys. I should have recommended 30v (or 6v increase).

Ultimately it depends on your goals which you want to do. If your primary goal is more speed, and you are not very concerned about frying a $20 controller, and a $50 motor (according to www.tnscooters.com prices) then go for the 36v mod. If you are racing the thing, then go for a 48 or 60v mod and hope to do a few runs before the motor is toast, though this would fry the controller probably instantly. What are your goals? Are you focused more on reliable transportation with just a few extra mph than stock?

As a rough calculation (more a guess) I would expect a top speed something like this if 16 mph is the current top speed:
30v: 19 mph
36v: 22 mph

[url=/forum-topic/motorcycles-and-large-scooters/587-my-kz750-electric-motorcycle-project]KZ750 Motorcycle Conversion[/url]
[url=/forum-topic/motorcycles-and-large-scooters/588-fixing-my-chinese-scooter]900 watt scooter[/url]
Pic from http://www.electri

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