Power Module Overheat?

[F55]

I was out today tearing around on deep gravel and then sat stationary at a table for a good 30 minutes with a bit of tilt on. Afterwards I moved off for about 20 feet and the chair cut out, the screen went blank, switched off. I turned it back on and pushed the joystick forwards and it shut off again. I tried it 2 more times while guys I was with looked around for anything obvious. The next time I turned it on I selected tilt and it worked fine so I put it back down. I then selected another profile which is identical bar the maximum forward, reverse and turning speeds, it is my empty chair setting and it worked fine. I went back to my usual profile and it cut out again. After that I got back to my vehicle on the empty chair profile without a hitch.

I travelled home for 40 minutes and when I arrived I got out the vehicle on the empty chair profile to make sure I could. Once in the home I selected my usual profile and it worked!

Surely if the power module overheated I wouldn't be able to operate the empty chair profile either? I haven't yet checked the logs but there was no error showing on the controller, it just shut of completely.

Anybody else come across this?

[Burgerman]

Humans see causes and patterns where non exist. The chances of different profiles being the cause of the problem is extremely unlikely. Far more likely that there is a loose connection, oxydised crimp (dont crimp!) loose battery terminal or connector on the power module. Bad bus cable. Bad connection to or bad breaker. Heat causes the power module to roll back so you have little torque. Not a black screen and switch off. I doubt its got a thing to do with heat or profiles.

[F55]

I reported as it happened and doubting it could be heat or the module wouldn't work for any profile but no matter what the reason it wouldn't play ball on my usual profile only.

I'll take a look tomorrow and recheck everything. It has recently been apart plus it's had a new bus cable fitted.

[F55]

Update:
I got the chance to check over the issue where the chair would work sporadically then unceremoniously stop and attempt to throw the occupant out of the seat. It cut out today a couple of times when testing and then on the 3rd attempt it wouldn't turn back on. This made diagnosis a bit simpler because my USB plugs still worked so it more than likely wasn't a battery fault.
We replaced the brand new bus cable with my old bus cable and it's now working without a hitch. So much for brand new replacement parts! Still, I have more cables on their way to replace my old cable and for spares.

I'm assuming it's just bad luck or is there any other reason a bus cable would fail, brand new or otherwise?

[steves1977uk]

Could be oxidisation in the yellow bus plugs. De-oxit works wonders on dirty pins. Check the male socket on the PM and joystick for manky looking pins, and any others like the ISM.

Steve

[F55]

Could be oxidisation in the yellow bus plugs. De-oxit works wonders on dirty pins. Check the male socket on the PM and joystick for manky looking pins, and any others like the ISM.

Steve

All looks clean, Steve, but it won't harm to 'wash' them.

[F55]

Damn, unfortunately it wasn't the case despite travelling much further than before although that just made it worse to call for the back up chair to be sent out! Sitting stationary in a village for 20 minutes isn't my idea of fun. Anyway, it was pushed home and sits in the garage waiting for when I can muster up the love for it again.

As I lurched forward violently and very nearly fell out I thought I saw a message come up on the controller. It said something like " 1 high battery" or am I making it up? To be honest the shock of just holding in the chair was my first concern.

[fishinjunky]

Humans see causes and patterns where non exist. The chances of different profiles being the cause of the problem is extremely unlikely. Far more likely that there is a loose connection, oxydised crimp (dont crimp!) loose battery terminal or connector on the power module. Bad bus cable. Bad connection to or bad breaker. Heat causes the power module to roll back so you have little torque. Not a black screen and switch off. I doubt its got a thing to do with heat or profiles.

Yea I over heated my power module today. I have a waterproof cover on it but it got way to hot I couldn't go up any hills at all but and your right no black screen or shutting off just no torque. I had to remove the waterproof cover

[steves1977uk]

Yea I over heated my power module today. I have a waterproof cover on it but it got way to hot I couldn't go up any hills at all but and your right no black screen or shutting off just no torque. I had to remove the waterproof cover

Surely you must've seen the air vents on the PM??? Where's it located to be able to get wet?

On my modded chair the PM sits on top of the battery box under the seat, so no chance in getting wet in the rain. And plenty of airflow around it.

Steve

[Burgerman]

Surely you must've seen the air vents on the PM???

No. Where?

Only where the connectors go. That might leak.
viewtopic.php?f=2&t=8857 pictures...

[fishinjunky]

Yea I over heated my power module today. I have a waterproof cover on it but it got way to hot I couldn't go up any hills at all but and your right no black screen or shutting off just no torque. I had to remove the waterproof cover

Surely you must've seen the air vents on the PM??? Where's it located to be able to get wet?

On my modded chair the PM sits on top of the battery box under the seat, so no chance in getting wet in the rain. And plenty of airflow around it.

Steve

when i had someone put it on i didnt get a real good look. My linx PM is mounted on the battery box behind the seat. Somewhat in the open but not the connectors theyre more protected but i was concerned about the PM getting wet but where its located i now think it will be fine. it a bounder 300m

[fishinjunky]

Surely you must've seen the air vents on the PM???

No. Where?

Only where the connectors go. That might leak.
viewtopic.php?f=2&t=8857 pictures...

the connectors seem to be protected the way its mounted but the rest of the PM is somewhat in the open mounted on the battery box. Do you think i should be ok as far as chances of it getting wet and going out. it a linx PM Bounder 300m

[foghornleghorn]

To be honest the shock of just holding in the chair was my first concern.

Seatbelt. Seatbelt. Seatbelt. Seatbelt. Seatbelt!

Damn, unfortunately it wasn't the case despite travelling much further than before although that just made it worse to call for the back up chair to be sent out! Sitting stationary in a village for 20 minutes isn't my idea of fun. Anyway, it was pushed home and sits in the garage waiting for when I can muster up the love for it again.

As I lurched forward violently and very nearly fell out I thought I saw a message come up on the controller. It said something like " 1 high battery" or am I making it up? To be honest the shock of just holding in the chair was my first concern.

- Overheating I find the chair gets slower and slower until it goes on strike and wants you to sit under a tree for a while to let it cool down. Once it's cooled, back to normal driving. Also to consider- I also managed to overheat a chair one day while having a rest parked with the exposed brain cooking in the midsummer sun

- Sudden instant stopping and attempting to throw you out the front of the chair for me was when I had a loose electrical connection. The parking brakes that go on and off with a loud click are usually only there to hold you still once stopped. They hold tight when there is no power, and release when you give them electricity at 12v or 24v depending on the type. Take away that brake releasing electricity even for a fraction of a second while driving and they lock on instantly, stopping you dead. If it is just an intermittent bad connection it can happen at any time and be perfectly happy afterwards until the next time it randomly decides to kill you.
- hunt for loose connections, or a lead with broken internal wire(s)
- the only thing I'm wondering other than that is the "1 high battery" message you think you saw. If brakes experience a low voltage rather than the extreme of 0v maybe that will stop them too? Could be 24v brakes suddenly seeing only 12v killed you if one of your batteries is on the way out.

[F55]

Seatbelt. Seatbelt. Seatbelt. Seatbelt. Seatbelt!

It pretty well had the same effect without the belt on anyway. I just folded in half with my face almost touching my knees.
I think with the seatbelt on the chair would have lifted up at the rear with my body slammed against the seatbelt and I'd have barrel rolled.

- Overheating I find the chair gets slower and slower until it goes on strike and wants you to sit under a tree for a while to let it cool down. Once it's cooled, back to normal driving. Also to consider- I also managed to overheat a chair one day while having a rest parked with the exposed brain cooking in the midsummer sun

- Sudden instant stopping and attempting to throw you out the front of the chair for me was when I had a loose electrical connection. The parking brakes that go on and off with a loud click are usually only there to hold you still once stopped. They hold tight when there is no power, and release when you give them electricity at 12v or 24v depending on the type. Take away that brake releasing electricity even for a fraction of a second while driving and they lock on instantly, stopping you dead. If it is just an intermittent bad connection it can happen at any time and be perfectly happy afterwards until the next time it randomly decides to kill you.
- hunt for loose connections, or a lead with broken internal wire(s)
- the only thing I'm wondering other than that is the "1 high battery" message you think you saw. If brakes experience a low voltage rather than the extreme of 0v maybe that will stop them too? Could be 24v brakes suddenly seeing only 12v killed you if one of your batteries is on the way out.

Thanks for your input. I'm waiting for someone to come and take a look at the places I can't which is frustrating enough without not being able to use the damn chair. If I switch it on now it'll let me possibly recline it a bit then cut off. Sometimes it's 10 minutes before the controller turns back on or sometimes it's overnight but on any occasion it cuts out within a second or so.
Anyway, it will be looked at and hopefully fixed. Changing a brand new bus cable for another brand new one did the trick for 20 minutes which in itself is odd. We really thought we'd fixed it.

[F55]

Hopefully it's sorted now! On inspection the battery connections on 1 battery terminal were loose. The bolt was tight but the connectors were flapping if gently touched. On checking the other 3 terminals a similar occurrence to a lesser degree was apparent. The bolts on all 4 terminals were as tight as possible so we removed them, drilled and tapped a new thread allowing for bolts to tighten the connectors as they should be.

I did, tentatively at first I must say, a mile around my garden without fault. That is the furthest the chair has been without abruptly stopping since the intermittent fault appeared. The last 10 minutes or so I did give the chair some stick, wheelies, abrupt stops and flat out acute turns to give it a real test and all appears fine.

I also managed to read the joystick logs now it remained on and there was a 'High Battery' and 'Low Battery' error showing.

[Burgerman]

Burgerman wrote:
Humans see causes and patterns where non exist. (heat, different profiles etc).
The chances of different profiles being the cause of the problem is extremely unlikely. Far more likely that there is a loose connection, oxydised crimp (dont crimp!) loose battery terminal or connector on the power module. I doubt its got a thing to do with heat or profiles.

Physics. Logic. Reason. Not personal testimony, opinion, patterns where there are no statistical REAL patterns in spite of what you "feel" or think or have convinced yourself of, no woo woo, or any of the rest. Only physics logic and reason work. Empirical evidence. Logical testing and reasoning.

I dont mean in this case here. I mean in EVERYTHING in life. The only way to the truth.

LOGS 1. The only way to get a low battery error with a charged healthy battery is a BAD CONNECTION.
LOGS 2. The only way to het a high battery error is if the chair is slowing as it will with a battery disconnection, and so REGENERATING power and a bad connection means it cant dump this energy to the battery. So regen voltage spikes high. This can take out the power mosfets...

[F55]

Fortunately I've been around long enough to realise that but at the same time you will always have to rethink patterns to give yourself somewhere to start.
It was Foghornleghorn's reply of experiencing exactly the same that helped.

[Burgerman]

Yes I realise that. And that high batt volage warning you thought you may have imagined as you were falling out was another clue. Short of being struck by lightning theres only ONE cause.

LOGS 2. The only way to get a high battery error, is if the chair is slowing as it will with a battery disconnection, and so REGENERATING power. And a bad connection means it cant dump this energy to the battery. So regen voltage spikes high. This can take out the power mosfets...

Any pattern or clue can lead you to diagnose or test for a real problem. Or it may just be a confirmation bias if you dont apply logic and reason to it.

Like my mum KNOWS that burying that liver in the garden got rid of a wart. Because it worked "for her"... And she thought that every time she thought of her mum the phone rang and it was her. She thought she was gifted in some way and could predict it. Why did she think this? Because she only remembered the times when that worked. And was ignoring all the times when she thought of her mum and it did not ring... The typical confirmation bias.

So a pattern or clue may help. Or may be imagined or mentally biased. Or seeing patterns with inadequate data. It may help point to what to actually test scientifically to find the truth if its real. Or the fault. On its own it proves nothing no matter how much it convinces you. Again I dont mean this problem I mean everything in life.

[F55]

Ultimately wheelchairs aren't rocket science fortunately and once stripped down to view the essentials and possibly swop out the PM, bus cable, joystick, look at and test batteries, hook up a spare motor you'll pretty well have found it. Broken wires in the middle can be more of a pain I can imagine but again not difficult to find once the chair is broken down.

My mate buried his wife in the garden believing it would get rid of his stress. It appears he was right, he's so chilled and happy go lucky now.

[Burgerman]

I presume she was dead? Are you allowed to do that? You dont have to bury them. You can just move them out and get a new younger fitter one thats easier on the eye. Same stress. But at least its worth it.

[F55]

No, she wasn't dead when he put her in the hole but he said that was half the fun. I don't think it is legal but then "speeding isn't and we all do it" was his reply if asked.
Moving them out isn't the same though, they are still breathing. He looked at is as doing a community a service by preventing anybody else from suffering. He is an honourable guy.

He now has plenty of fit, younger girls visit him but they always leave, I think.

[Swan T.W.]

I presume she was dead? Are you allowed to do that? You dont have to bury them. You can just move them out and get a new younger fitter one thats easier on the eye. Same stress. But at least its worth it.

That's very expensive to do!!

[Burgerman]

Can be. Not always. The last one I moved in stayed 10 years or so, was young, attractive no baggage, worked as a teacher teaching maths to degree level at the college/schools and filled my fridge, etc and still does! In spite of leaving, then marrying someone else. Still see her all the time bearing gifts! Never cost me a penny - quite the opposite. All she ever wanted was for someone to marry her. I am not really in that position. So she went off elsewhere...