PINNED - R-Net for dummies

[Burgerman]

Why would you expect them to know anything? I expect them to get most everything wrong. MOST PEOPLE are stupid. Most sellers are only interested in sales. Most people have the attention span of a 2 year old. They listen to the first 5 words and they "know" it all..

Try going to the mcdonalds and ordering a burger without that green thing. Or without mayo.
I garantee you will get the wrong thing. Over and over. Been doing that for years. You get plain burger. Burger with no cheese. Burger with no fries. Wrong meal altogether. Is too complicated for them. They do not listen. They hear 3 words and make up the rest.

Average IQ is 100. Thats already pretty dumb. The average person is not very bright can barely make up a logical sentence. And HALF the population are below even that level by definition... And this nonsense they all shout loudly about on social media or garbage websites meant as ad revenue farms is where AI gets its "knowledge" from. So ignore that garbage too.

I have a VERY CLEAR repeat prescription with 6 items. Quantity. Item name and ID number. I send that to my doctors by email every 28 days. In 29 years it hasnt changed. The doctors get it WRONG approximately half the time. Forget to process it avery 4 or 5 times. Send it to the wrong supplier (which I clearly marked) 3 or 4 times a year. When I call to tell them they failed yet again, they say I am rude. I dont swear I dont raise my voice. I just point out that they failed yet again to do the same simple thing. They hang up, they send me threatening letters accusing me of abuse etc. What is really happening is that they are too STUPID to do a trivially simple thing correctly. And when I point that out that makes ME the problem...

[g1ddyup]

So if the batteries were plugged with the joystick come on? Or do the motors need to be plugged in also? Thanks

[Burgerman]

It can be powered up without motors connected. But it will show an error code. You can still program it, if you want.

[emilevirus]

You can do even better. Just power it using the XLR charge port. That's what I do to program it. You don't even need a battery then.

[Burgerman]

You can do that. With a few provisos.

A typical mobility charger wont work unless it sees above 18 to 20 volts.
A set of batteries will work, but on start up there are some big capacitors inside that cause a big spark and a very high momentary current of much more than that 12A charge port, and joystick wiring were designed for. So you might damage something.

Perfectly safe if you use a low current 24 to 28V power supply like for e.g the ZXD with max current set between 4 and 12A. Not more.

[emilevirus]

You will need to split them. Or run from 1 side, and add a relay.

I added a 24v relay, lights set to 24v. It works but relay is buzzing like crazy and lights are flickering. Any idea why?

[shirley_hkg]

How about Parallel a small cap across it .

[Burgerman]

Yes.
Because it takes battery voltage like 26V or so and regulates it to 12 or 24V. By doing the exact same thing as the motor controller, it is a pulse. Lets say you have 24V battery. And wanted 12V out. You take a typical frequency, like 10 to 20 thousand times per second, that you can hear. And you switch a signal ON 50% of the time off 50%. That gives an average voltage of 12V. Yes ideally a small capacitor across the relay. And a resistor in SERIES before the capacitor.

25% on = 1/4 battery voltage.
50% = half batt volts.
75% = 3/4 of the battery volts.

You are getting about 95% so its turing the relay off 5% of the time.

[emilevirus]

So I tried without relay and it works. Not sure if I can break something. Max is 40W and I use like 50w.

[Burgerman]

Its meant for incandesent bulbs. A 21W bulb takes around double that before it heats up so it should be OK if your 50w is LED..

[emilevirus]

Fine then. I'll remove the relay. Another question: I have a 24v to usb 5v converter connected to light output. Will it be affected by the pulsed DC?

[Burgerman]

If you add a simple capacitor nothing will be effected. I dont know if it will be affected because I dont know how it works. But it wont like it.

[Burgerman]

Remember that most inverters or even the AC in your wall are not constant voltage.

The PL8 for e.g "chops" the supply voltage on and off and has a choice of 3 different frequencies to choose from.

The AC in your house isnt really 240V as caimed its a sine wave. Its POS 355V then 0V then minus 355V and this repeats at 50 or 60 cycles per second. We call that 240V as thats its average voltage.

[emilevirus]

I ended up just connecting the lights as intended. They flicker... Why would they do that if it makes LEDs flicker? Why don't they add a cap? My old chair was flickering as well. I thought lights were going bad but now I know why. I suppose it's due to lithium as voltage is higher?

[Burgerman]

No its due to the fact that they send 24 or 12 volts. From a battery with a higher voltage. By switching it on/off. So that the AVERAGE voltage is correct. The same way they control the chairs motors. Pulsewidth.

The reason the flicker is that they use a constant frequency. That was originally intended to be used on a filament old style bulb. Thee smooth out the pulses as they heat up and cool down an element. And its got thermal mass. So the frequency they chose was quite low. Slow enough that you can see the on/off on an LED as those are instant. The reason for a low frequency is that it gives better efficiency.

[emilevirus]

Output voltage is actually 22v. I suppose it's to prevent lights to dim when under load. There should be an option to turn that off. Who uses bulbs nowadays?

[Burgerman]

It was designed 25 years ago though. Chairs then gradually adopted LEDs which actually work as diodes because they are diodes. Even at super high frequencies. that LED sees the full voltage. Even when set to 12V. It still sees the full battery voltage. On and off around 40% of the time. Does it hurt them? I think it does/should. Adding a capacitor will stop the flashing. But will INCREASE the voltage. As it will charge to full batt voltage. Most people are not sensitive to it and dont care though. I think they use a frequency that you would hear if it was connected to a speaker.

My dog could easily hear my chairs motors drive frequency (about 16k) because he used to jump up and move even if I added a tiny bit of power but not enough to move the chair. With no brake working. I turn those off indoors.

[Mr TT]

I want to purchase a Small pod, actuator and 120 amp power module X 2 2 pair with those 8 mile-per-hour motors you have on the BM, I forget their name. Is there any way I can purchase them direct from the manufacturer, r-net?

[Burgerman]

Motors? Or R-net stuff?

I opened an account with PG Drives in order to buy an OEM programmer in 97...
I have ordered various things over the years since.

Generally I dont bother as I find ebay 10x cheaper inc for new stuff and joysticks as long as you are in no hurry and are prepared to fish eBay properly.

I never pay more than £40 for lighting modules. £45 for 120A power modules all used but as new.
125 to 150 for new boxed CJSM2 joysticks. 80 for CJSM(1) joysticks. 40 to 50 for LED joysticks.

So dealing with PG seems only required if you want obscure stuff like the IO module or something.

Motors? Look at the JIVE 8mph linix ones on the sunparts site, grab the serial part numbers and order from any sunrise dealer.
Sunrise or other chair manufacturers as spares.

£90 total, inc cables and seating/lighting module...

[Mr TT]

https://www.ebay.co.uk/itm/155352918889
On one of my wheelchairs, which has a 120 power module, these lights are incredibly bright — easily the brightest wheelchair lights I’ve used. They work so well that when I’m travelling on the pavement, I sometimes have to lower the footrests because otherwise the lights can dazzle pedestrians.

The problem is that when I fit the same lights to my other wheelchair, which also has a 120 power module, they behave very differently. At first the LEDs show a blue tint in the centre and are noticeably less bright, and after a short period of use they fade even more.

Does anyone know what might cause this, or whether there’s a way around it?

[emilevirus]

Probably one was set at 24v, other at 12v. Program it to output 24v.

[snaker]

Can you help me to check if this PM is generic PG or Permobil?
https://www.ebay.com/itm/198203212579

And can you help me to search a r-net joystick like in the below image (having extension cable, no screen, less buttons). I can buy from ebay US/CA/UK/Germany. Maybe ebay filters search result by my ip, I only find a couple of items and they cost $200 or more.

[emilevirus]

The PM is a Quickie so it's fine. Here: https://www.ebay.com/itm/366300601212 but it's used and dirty. You have to be patient. You may find a brand new one for as cheap. Just keep looking every day and you'll eventually snag one.

[emilevirus]

What happens if I increase the current boost limit past its theorical max i.e 130A? Will it just overheat and throttle down or something more serious could happen?

[Burgerman]

It will error on load. Or not exceed 120 anyway.

If motors are high impedance it wont reach 120 even if you fitted a 500A controller.

[emilevirus]

Manual seems to suggest it allows it: WARNING:
The values in the table above should never be exceeded. Doing so will invalidate the warranty and affect the long-term
reliability of the Power Module.

The MOFSETS are able to handle much higher current than 120A. The new PM2 controller is 140A. It makes me think they increased the limit without changing any components inside.

[Burgerman]

Watch the screen, watch motor amps, I doubt bounder motors at that impedance reach 120 anyway. Even if it let you set it. I never tried but but I would be surprised.

You cant set motor current above 100
You cant set booes current above 120

Just tried it. Says "illegal" ...

[emilevirus]

I did it... Anyone has a PM laying around willing to risk it?

[Burgerman]

Well I cant!

But as I say. I doubt your motors will pull 100A. If they do it will only be when not moving (stalled).

Do a screenshot while testing it. Like below.



Even on older chairs like this below I see it max out its 100A (100A unit) capability on turns (or ramps/curbs) at 100A+
ONE motor. Watch carefully. https://www.wheelchairdriver.com/gopro/motoramps.mp4
See if it does this. I very much doubt it. Which means it doesent matter what you set motor amps to as it will never pull this many amps. A controller doesent send amps. The motor PULLS them if they are low enough impedance.

On R-Net:
Note CURRENT: M1 and M2. Here I saw 114A and 102A while turning right in my house. While turning on a thick carpet. With high turn acceleration it sees 120A all the time. Watch what your does. It will probably be lower.

[emilevirus]

Here if you'd like to try it. It pulls 100A+ quite frequently actually.