WARNING!!! PLEASE READ IF YOU HAVE A XLYTE CONTROLLER

[knoxie]

Hello

I had another controller come in for repair I checked it with my meter and it was clear from testing between the blue motor phase and the battery terminal that 2 of the high side fets were stuck on blown if you like.

So i stripped the controller and replaced the fets and the associated high side transistors, I tested the controller it all worked fine, so i screwed it all back together.

However when I tested it again it started up full throttle straight away!! scary!! so i tried another throttle, same thing full throttle again.

I stripped the controller back down and checked the fets tab to the screw holding it in, 2 of the low side blue phase screws were shorting to deck so I fixed that (thinking that was the problem) re assembled the controller again and bang it did it again.

Erm so no to be put off I played with the controller a little, it would stay full speed as soon as it was powered up, however just by chance I moved the throttle lead and it stopped, I then held the lead firmly in this position and tried the throttle, it worked fine to my surprise.

I then examined the throttle lead and it became clear with a bit of DVM work that the lead was shorting inside!!

I stripped back the insulation and sure enough half way down the cable the wiper input was picking up 5volts off a break in the lead, see the attached photos.

not having any more plugs I cut a piece of cable and painstakingly removed all the pins and re crimped and soldered them to a new cable as you can see in the pictures.

I dont know why this controller came in for repair, it may have blown though as someone was frantically trying to stall the motor, scary stuff.

So its worth checking your wiring but more importantly fit an emergency rip cord or something as on little scooters you just wont stop it.

See the pics

This controller is a happy unit again now.

Cheers

Knoxie

 

[xyster]

Knoxie, are you using the throttles with the battery metering LEDs? Those are known to have particular problems shorting to the extra power wire, particularly after getting wet.

I bought the LED-less throttle and sealed it with silicon. Thankfully, it's worked in the wet without problem yet.

 

[knoxie]

HI Xyster

This may have been the problem I don't know if the person was using an led type throttle.

I prefer the no led type throttles as well, also you cant use a fixed type led throttle if you play around with different voltages as I do.

It may have been a combination of that and also the cable was kinked as well, either way it was scary in that it just stuck on full throttle.

Thought I would bring it up, good point you made there though Xyster, I would ditch the led throttles if they can cause this to happen.

The new cable i fitted is much thicker and better quality.

Cheers

Paul

 

[safe]

I bought those "cheap" throttles from TNCScooters and two of them shorted out and made my motor stuck at full throttle. What seems to happen is that the Hall Effect sensor on the cheap throttles is extremely sensitive to voltage and can fuse togther somehow (internally) and you get full throttle as a result.

So I'm being extrememly careful not to allow the throttle wires to touch anything that might have any current in them.

They ought to build those things better... (but at $7 what can you expect?)

 

[knoxie]

Hi

Yes maybe a fuse would be a good idea as full throttle with maybe 2.5kw at 72V could really hurt you or even kill you at the very worst.

I am not sure if this was the throttle or a cable fault or maybe a combination of the two, either way its pays to have a backup to kill the controller should you need to.

On the BMX with the Puma you just wouldn't stop it on the brakes should it do this, you would have to jump off the back or somehow get the front wheel off the ground.

I have no doubt the cheap throttles are a problem, that's why i use magura throttles and have never had any problems.

Cheers

Knoxie

 

[fechter]

Good detective work Knoxie.

It's kind of ironic that one of the main reasons I switched to a brushless system is to reduce the likelyhood of a WOT failure. If a FET shorts, it pretty much stops the motor. I was seriously injured by such an event on my Zappy, which blew a FET and went full throttle suddenly.

I also use a kill switch mounted in the throttle housing that can be easily switched by my thumb, much like a gas motorcycle.

With a Crystallyte controller, it's pretty easy to extend the main power switch out to the handlebars. Mounting a switch on the handlebars is a bit more challenging.

 

[mr.electric]

My friend was test driving my high powered scooter and crashed. The hall type throttle broke apart and the rotating sleve with the magnet broke away leaving the stationary portion of the throttle on the handlebars. I was surprised that the scooter was stuck on WOT. I guess the throttle needs to see a magnet close to one of the hall sensors to send a no throttle signal.

 

[mr.electric]

My friend was test driving my high powered scooter and crashed. The hall type throttle broke apart and the rotating sleve with the magnet broke away leaving the stationary portion of the throttle on the handlebars. I was surprised that the scooter was stuck on WOT. I guess the throttle needs to see a magnet close to one of the hall sensors to send a no throttle signal.

 

[knoxie]

Hi Richard

Yes I agree it is a good idea to rig or extend the power switch up to the handle bars, I may do this on all my rides having seen this happen on the controller.

I will look out a nice cheap waterproof switch and wire it in series with the controller, it needs to be right where your thumb is so you can instinctivley push it should the worse happen.

On a 26 inch wheel bike you may hold it on the brakes if they are good brakes, you still need to do something though and thats the kicker, your instincts will make you hold on for grim death it sounds like you had a similar situation, as with a perm motor and controller a stuck fet is very bad news indeed.

Its a shame they dont fail safe, this isnt a stuck fet its a stuck throttle, I think we would all be wise to install a kill button.

Cheers

Paul

 

[rkosiorek]

since you just need to disable in an emergency why not use the controller's built in EBrake connector and a small switch with some small wires that are easy to mount to the handlebar?

on the EBrake connector shorting pins 2 and 3 together will stop the motor by disabling the internal PWM.

 

[knoxie]

Hi Rick

Yes good Idea must get something done, I have since found out what happened with this controller.

The chap using it had put 72V on it and had the 48V led xlyte throttle in, the controller blew very quickly, I had the same problem I blew one of those throttles in the early days as I didn't think it would be a problem at 72V stupid really as of course they would have a problem.

So it may have been this that caused the problem in the cable I think, it still pays to put an emergency stop of some sort in place, Ill get a thumb switch in place for sure.

Have a good week

Knoxie

 

[fechter]

since you just need to disable in an emergency why not use the controller's built in EBrake connector and a small switch with some small wires that are easy to mount to the handlebar?

on the EBrake connector shorting pins 2 and 3 together will stop the motor by disabling the internal PWM.

Many controllers are set up this way. Applying the brake simply shorts out the throttle input. You need brake levers with switches. On my Vego, I took these off because I upgraded the levers. It also makes it hard to do a burnout. Another possible way to have a switch would be to use a magnetic reed switch or microswitch mounted on the brake caliper that gets activated by the brakes. This way you don't need special levers. I did something like this on my Zappy.

 

[knoxie]

Liking that Idea Richard as its easier for me to implement as well, also I have loads of those switches lying around. I must get something done, the connector is there on the lead there is no excuse for me not to connect to it.

You can never have enough safety features on a bike.

Cheers

Paul

 

[rkosiorek]

on the 3525A PWM chip pin 10 is a shutdown pin that inhibit the PWM. the ebrake as well as the low voltage cutout and the stalled motor error pull this pin down to stop the controller from operating.

i insist on using EBrakes on all of my bikes. and i hate to say but usually the bakes supplied with kits suck big-time. the only ones that are reasonable are the mechanical ones that come with the Cyclone kit. but even then i often want to use the existing brake lever on the bike. for that reason I put together some parts that i use to add to the existing lever. i use some neoprene rubber and industrial grade peel and stick.

i have more photos on http://www.flickr.com

http://www.flickr.com/photos/81573562@N00/sets/72157594353874522/

or

http://tinyurl.com/vvey3

 

[rkosiorek]

i guess i mighta made those photos too big. sorry guys. i'm not familiar with this type of forum is there any way to reduce the size of these short of deleting and re-posting?

 

[Lessss]

edit the post, remove the pics, resize the pics then repost the pics.