Search found 1116 matches

by Gregory
Feb 11, 2018 10:22 pm
Forum: Motor Technology
Topic: 2 controllers in paralell for one hub motor, is it possible?
Replies: 31
Views: 559

Re: 2 controllers in paralell for one hub motor, is it possible?

Samd was posting that he'd had some successes using two controllers a couple of years ago, but no follow up on actual road use and longevity. Personally I'd just get a bigger controller. :D

https://endless-sphere.com/forums/viewt ... =2&t=75186

by Gregory
Feb 11, 2018 10:08 pm
Forum: E-Bike Photos & Video
Topic: Making a carbon fiber swingarm
Replies: 4
Views: 589

Re: Making a carbon fiber swingarm

I assume it to be annodised Al.
by Gregory
Jan 28, 2018 8:41 pm
Forum: E-Bike Technical
Topic: 96V Charger in Australia
Replies: 3
Views: 144

Re: 96V Charger in Australia

120v DC boost converter?

https://www.ebay.com.au/itm/Digital-LED ... SwokJaVI9s

Or two meanwell 48v supplies in series and turned up to 54v each?
by Gregory
Dec 19, 2017 10:28 pm
Forum: E-Vehicles General Discussion
Topic: I may be building an electric go-kart
Replies: 11
Views: 438

Re: I may be building an electric go-kart

No you don't add the Ah with the cells in series, only if you parallel 6 batteries would you get a 12v battery of 240 Ah capable of 720 A.
by Gregory
Dec 19, 2017 5:58 pm
Forum: Motor Technology
Topic: MOSFETs near their voltage limit
Replies: 4
Views: 224

Re: MOSFETs near their voltage limit

As an amateur I use 20% for MOSFETs and 50% for caps.
by Gregory
Dec 18, 2017 8:15 pm
Forum: E-Vehicles General Discussion
Topic: I may be building an electric go-kart
Replies: 11
Views: 438

Re: I may be building an electric go-kart

Love the idea of a go kart. I can't speak to gear ratios. Those prismatic batteries are only good for 3 or 4C continuous discharge. So maybe 150A tops continuous. Which may be OK for your plans. I think they would get hammered on a race track. Any higher and you could be replacing them every season ...
by Gregory
May 18, 2017 4:31 am
Forum: General Discussion
Topic: Legends dropping like flies
Replies: 160
Views: 15443

Re: Legends dropping like flies

Chris Cornell from Soundgarden & Audioslave found dead. No other details yet.
by Gregory
Apr 26, 2017 8:08 am
Forum: E-Scooter and Motorcycle General Discussion
Topic: Repairing controller 2v problem
Replies: 7
Views: 341

Re: Repairing controller 2v problem

The first thing I'd check is the battery in my multimeter.

Then find the 5V voltage regulator on the board, probably a tiny sot23 SMD part (or maybe a TO220 like a MOSFET) . It will be connected in line with/close to the main power in.
by Gregory
Apr 16, 2017 8:59 pm
Forum: E-Bike Technical
Topic: 72V (20S) to 5V switching power supply?
Replies: 5
Views: 238

Re: 72V (20S) to 5V switching power supply?

Many ac/dc wall wart style phone chargers work fine on higher dc voltages. Have you considered those?
by Gregory
Apr 12, 2017 4:22 am
Forum: E-Bike General Discussion
Topic: How can I discharge a battery to certain voltage?
Replies: 4
Views: 241

Re: How can I discharge a battery to certain voltage?

Battery medic will discharge cells down slowly.

Or CellLog 8M has an output for an alarm that can be modified to trip a discharge like a bank of globes. Will stop when the lowest cell hits the trigger point.
by Gregory
Apr 08, 2017 10:43 pm
Forum: Stand-up E-scooters and E-skateboards
Topic: longer battery wires or longer motor wires
Replies: 16
Views: 1047

Re: longer battery wires or longer motor wires

And this is a post responding to John that illustrates it well.
by Gregory
Apr 08, 2017 10:24 pm
Forum: Stand-up E-scooters and E-skateboards
Topic: longer battery wires or longer motor wires
Replies: 16
Views: 1047

Re: longer battery wires or longer motor wires

I read years ago that battery wires should be short. And I've tried to stick to that in my builds, but within reason. Quality capacitors on the battery wires deal with the majority of issues caused by the inductance. Shortening the battery wire by 2cm on a skate board probably won't have any appreci...
by Gregory
Mar 10, 2017 11:37 pm
Forum: Battery Technology
Topic: LifePo4 voltagedrop, is this normal?
Replies: 15
Views: 655

Re: LifePo4 voltagedrop, is this normal?

1. Assuming 16S, turn your charger down to 58.4V if possible, or buy a new charger. Most BMS will balance at 3.65V per cell. 2. 12V sag is excessive. See if one cell voltage is sagging worse than others indicating it is faulty or decrease your current draw. If the battery is made of the worst chines...
by Gregory
Feb 20, 2017 4:36 am
Forum: E-Bike Technical
Topic: Can someone tell me which ebike this is?
Replies: 10
Views: 490

Re: Can someone tell me which ebike this is?

Looks like a geared bafang hub motor. Almost certainly 36V. Should have some info stamped on it?
by Gregory
Feb 19, 2017 6:37 pm
Forum: Battery Technology
Topic: 10Ah IN, 7Ah OUT?
Replies: 17
Views: 542

Re: 10Ah IN, 7Ah OUT?

Yes. Just stick the watt meter in between the battery and charger, and charge it up. No need to guess.
by Gregory
Feb 05, 2017 11:29 pm
Forum: E-Bike General Discussion
Topic: new eZip motor
Replies: 4821
Views: 275282

Re: new eZip motor

I'd be looking at at extending a frame longer to make it less prone to wheelies. Then using that extra space to mount the motor and batteries nice and low. Keeps weight low, keeps the belt away from your balls. Weight up high in the triangle seems like a problem. You should have already have read th...
by Gregory
Jan 30, 2017 6:01 pm
Forum: E-Bike Technical
Topic: Cheap LM2596HV dc-dc converters that BLOW UP
Replies: 7
Views: 372

Re: Cheap LM2596HV dc-dc converters that BLOW UP

Ha , nice fix , bet it tripled the cost of the board!

I'm pretty sure I received one with 50v cap across the input. I threw it in the scrap bin. But they are so irresistibly cheap. :D
by Gregory
Jan 30, 2017 4:47 am
Forum: E-Vehicles General Discussion
Topic: transformer chargin and why arent the lights flickering?
Replies: 16
Views: 654

Re: transformer chargin and why arent the lights flickering?

No the US uses 60Hz, but look at a sine wave (AC) and see how it crosses zero twice per period.

Thermal inertia is probably a more correct term.

Don't build this. Buy one or multiple isolated CC/CV 4.2v power supplies.
by Gregory
Jan 30, 2017 3:08 am
Forum: E-Vehicles General Discussion
Topic: transformer chargin and why arent the lights flickering?
Replies: 16
Views: 654

Re: transformer chargin and why arent the lights flickering?

Is this an isolated single cell charger to avoid balancing? what are my obstacles in going direct from the 120v ac and stepping down to 4.0 volts at the secondary, rectify, and charge? and do all the cells connected to the secondary in parallel and get balanced. For starters 1. Its a non regulated s...
by Gregory
Jan 19, 2017 6:38 am
Forum: E-Bike Technical
Topic: Removing lvc on 48v controller.
Replies: 17
Views: 581

Re: Removing lvc on 48v controller.

:D Sorry I can't help either.

If you're still open to advice, I'd stop focusing on changing the LVC and check the current the motor is pulling at no load. And what the voltage sags to.
by Gregory
Jan 18, 2017 5:37 am
Forum: E-Bike Technical
Topic: Removing lvc on 48v controller.
Replies: 17
Views: 581

Re: Removing lvc on 48v controller.

If I understand that correctly, I'd be looking at part of the battery either sagging down below cell level LVC (ie a bad cell) or going into over current protection. If the battery charges to 53V (same as the charger) then surely it's not controller LVC? More details like the battery, what LVC you t...
by Gregory
Jan 17, 2017 8:37 pm
Forum: E-Bike Technical
Topic: Removing lvc on 48v controller.
Replies: 17
Views: 581

Re: Removing lvc on 48v controller.

To mod the LVC, you will need to be able to disassemble the controller and solder. If you aren't confident doing that it will be easiest to buy a new controller. Maybe one with software programmable LVC and other parameters. Some controllers have pads with a resistor/link for multiple LVC options, m...
by Gregory
Jan 16, 2017 7:09 pm
Forum: E-Scooter and Motorcycle General Discussion
Topic: Motor runs for a second then stops
Replies: 9
Views: 368

Re: Motor runs for a second then stops

What are you using to power it?
by Gregory
Jan 15, 2017 9:21 pm
Forum: E-Scooter and Motorcycle General Discussion
Topic: Motor runs for a second then stops
Replies: 9
Views: 368

Re: Motor runs for a second then stops

First two things I'd look at are... Incorrect phase/hall combo. May be a false positive. Wiring colour to colour is NO guarantee of it being correct. or less likely, Battery voltage sagging down below LVC if it can't supply the required current. Should be no problem if you are testing no load (wheel...