Controllers for lightweight chairs

[emilevirus]

3 years ago I bought a lightweight power wheelchair from china. It uses 2x 5Ah lion batteries in parallel. Only weighs 17kg. It's awesome to travel. But the controller is awful. It has a very slow response time. I have R-Net controllers laying around but I guess it's overkill for two small motors and it'd make the chair heavier. I'd like a programmable controller ideally. What'd you recommend?

[Burgerman]

Is it a chinese brushless? If so normal mobility systems wont work.

[emilevirus]

It said brushless but nahh it's brushed, pretty sure. Motor wires is just a XT30 connection.

[Burgerman]

Only 2 motor wires?

If so then yes you can use a mobiity cotroller. You can use VSI or something that is an all built into the joystick. Will need OEM programming to set correct brake voltage, motor compensation etc.

[emilevirus]

Also, I now use my iCharger to charge the batteries. Stock charger is 1A and I charge at 10A. Do you think it's fine? Usually RC batteries can be charged at 1C just fine but these idk, I cant see the ratings. I can feel the BMS getting hot tho. It gives a nice boost. 10min charge and I'm good for a few miles.

[Burgerman]

Well that depends what cells are in that battery. Probably too high. Most 18650 cells such as laptop batteries CAN be charged at 1C but live a lot longer is charged at 0.2C as the spec sheets normally tell you. They also need to be stored less than full. And balanced accurately. And if charged at say 4.1V per cell will last at least 3x longer.

[emilevirus]

Yeah, it'll already be a huge upgrade being able to store them. And the iCharger already defaults at 4.1V for lion. BMS may not balance them until they're at 4.2v tho, I think they're 21700 as they're 5200mah unless it's 7s2p

[shirley_hkg]

That clearly means two 18650 cells @2600mAh.

I'd charge at 0.25C for safety sake.

That will be a problem if you charge it to 4.1V, while BMS starts balance ≥ 4.2v

[Burgerman]

If that is the case. Most balance all the time, like my laptop or rc transmitter.

And still no problem if occasionally charged full.

[hank]

Hi
Could anyone tell me if a Quickie Q50R lightweight wheelchair uses brushed motors
What i want to do is fit R net joystick plus PM to make it steer properly
looking for a lightweight indoor chair to replace my manual one as getting weaker now

[emilevirus]

PMDC is brushed. 2 wire is brushed.

[emilevirus]

If you fit R-Net, you'll need a switch because it always consumes a bit of power and your batteries will be flat if you let it sit a while.

[martin007]

If you fit R-Net, you'll need a switch because it always consumes a bit of power and your batteries will be flat if you let it sit a while.

I didn't know that detail.

What switch do you have Burgerman?

[martin007]

Is it a chinese brushless? If so normal mobility systems wont work.

What features do those controllers have to be so different?

[emilevirus]

Is it a chinese brushless? If so normal mobility systems wont work.

What features do those controllers have to be so different?

Brushless is very different. It has 3 wire and always uses the same voltage even if it's going slow. Brushed is just voltage variation that controls the speed, brushless is pulse.

[Burgerman]

The chinese brushless controllers are a bit like the RC steering in a toy for a child. A few lines of code, and they dont steer well. They are also almost impossible to access a programmer anyway.

The BRUSHED controllers made by PGDT for e.g, have decades of fancy coding, are very controllable, and can be programmed to steer well and you can get programmers.

You get what you pay for here.

As for draing power when turned off, ALL controls systems that I ever saw have a very small drain on the bateries when turned off. In the order of 4 to 12 mA.
You can fit a switch, trip the breaker, pull out the battery, add a "loop" on an anderson connector, or whatever to prevent this. But batteries also have a similar but smaller drain internally too. So even if you disconnect a battery with a plug, fuse, remove a cable etc then it will take LONGER but will still have a small continual discharge.

A lead battery that isnt 100+% fully charged will deteriorate faster than if it is kept full.
A lithium battery is the opposite. If its lithium, use it and if you need to store it do so at around 30 to 80% charged. They live longest when at around 50%. So storing above 50 and below 80 will mean that even if stored many months it will be fine!
With one possible issue. BALANCE! Each cell is different. Stored for a long time will unalance the pack. So charge fully (only way to balance) every 3 to 6 months. Then discharge back to around 70%.

All my lead batteries are stored on a LOW float. Or charged every 2 weeks at a NORMAL float charge voltage overnight.
All my lithium batteries inc laptops, power tools etc are stored at around 80%.

[emilevirus]

Well, 12 mA on a 10Ah battery is a lot. That's 2Ah a week! On the Chinese controller I currently have, I must turn it off. Otherwise 2 weeks later it's flat. I don't use that chair often either so...

[Burgerman]

Yes but those are lithium. Lithium doesent like being full anyway.
And if it does manage to discharge it completely over time those cells have a BMS that switches off power. Although thats not a great idea really at least it wont kill that battery completely! But the battery is removable on those. So just pull it out. However. The built in BMS in the battery ALSO draws a very small current and often on just 2 cells! Which is why the manual likely says charge before storing it or similar.

[emilevirus]

Yes but those are lithium. Lithium doesent like being full anyway.
And if it does manage to discharge it completely over time those cells have a BMS that switches off power. Although thats not a great idea really at least it wont kill that battery completely! But the battery is removable on those. So just pull it out. However. The built in BMS in the battery ALSO draws a very small current and often on just 2 cells! Which is why the manual likely says charge before storing it or similar.

Yeah but in my case, a lightweight chair I use only when I need it like once a month. If I leave the controller on, everytime I want to use it, it's dead so a switch is really needed in this case.

[Burgerman]

Can you just unclip the battery and lift it partly out?

[hank]

If you fit R-Net, you'll need a switch because it always consumes a bit of power and your batteries will be flat if you let it sit a while.

THANKS

[hank]

If you fit R-Net, you'll need a switch because it always consumes a bit of power and your batteries will be flat if you let it sit a while.

THANKS

ANY OTHER CHAIRS TO SWAP TO R NET WITH BRUSHED MOTORS TO USE BETTER THAN THE QUICKIE Q50 R

[Burgerman]

I am baffled by that.
What are you asking or saying?

[JohnnyUK]

Hi
Could anyone tell me if a Quickie Q50R lightweight wheelchair uses brushed motors
What i want to do is fit R net joystick plus PM to make it steer properly
looking for a lightweight indoor chair to replace my manual one as getting weaker now

I bought a new Q50R Carbon last year with the cheap Chinese motors and nVR2 controller, it's pretty uncontrollable but as usual we can't access the program. The motors are horrible gritty noisy 250W Brushless things.

I'd be interested to hear what it steers like with R-Net good luck to you. Can't use mine anymore so it's going on eBay

[biscuit]

access the program.

WoodyGB made me a connector that worked on the nVSI of my Vienna.

[biscuit]

can't access the program.

WoodyGB made me a connector that worked on the nVSI of my Vienna.

I thought the Q50R had a VSI?

[Burgerman]

If it has then its programable. Chinesium ones mostly dont, same basic folding chair as sunrise one with a chinesium controller.

I think you wont have room for an r-net controller power module even if your one is brushed.

[emilevirus]

Just ordered the connectors for motor & battery along with a led joystick. Will let you know how it goes. Mine doesn't have electromagnetic brakes so I'll need to disable that.

[Burgerman]

Never tried it but disable these top two...

[emilevirus]

Current limit can't be lower than 50A but if I set power limit to 50%, that should limit it to 25A right?