Do You run a Kill Switch?? if not? why not ?

[knoxie]

Hello

With the advancing power of some of the rigs on the forum here I was wondering just how many of you are thinking of safety at the same time? whilst not wanting to lecture anybody I don't seem to see too many of the high power rigs with any kind of kill switches? you know who you are!! I run kill switches on all my rigs now, if you have ever had a throttle failure and a controller go off by itself then you may have already fitted a kill switch.

The best way of course is to fit some kind of solenoid and use a switch to kill it, it seems not many people are taking advantage of the already installed features of the controllers though, the Xlyte controllers as do most come with this feature built in, and by simply connecting a switch across the break input you can stop the controller should your throttle fail (this happens more often than you may think, I have seen a few controllers where the throttle unit has failed (usually those types that utilise the 5V on the throttle line for leds and the like but mainly the battery sense throttles that monitor the battery directly, they arent fused! , when these fail they can pull sufficient current up the throttle wires melting the insulation and causing shorts through the wires, seen this twice now.

Skulking aroung ebay you can pick up simple bar switches such as the one below fitted to the BMX, this is one of those pit bike kill switches, the top thinner button is pressed in allowing the bike to run, pressing the bigger button in kills the controller (contacts make), I have fitted these switches to all my rides now.

So come on fess up have you fitted a kill switch, if so please show us your setup here!! you never know it may save your life some day!! thats not too light a statement to make, ask fechter about his scooter when that went on him!! it hurts big time!!

Heres the BMX and its shiny new kill switch, the colours vary on the xlyte controllers, sometimes its the green and yellow wires, last one i did it was the black and green wires, just try twisting 2 of them together quickly first to find out which ones work.

Knoxie

 

[NickF23]

Good post Knoxie.

I really feel its just a matter of numbers before someone gets seriously hurt or killed from this kind of failiure. It applies less to very low power ebikes that can be stopped with manual brakes, but for higher power ebikes its essenetially a matter of time, more riders more journeys eventually someone will have this kind of failiure and be unable to stop for traffic lights or be sufficiently distracted enough to miss a serious and otherwise obvious lethal danger.

For this build I'm using a big chunky key switch on the D frame just below the handle bars it connects to the main battery. very easy to tap it when riding.

 

[knoxie]

Hi Nick

Yes that will do the trick! I would run a bigger fully rated kill switch If I had the room, I am pretty happy relying on the controller inhibit for now, you are quite right std legal bikes if you like prob dont need them but then in the uk you just stop peddling that should do it :lol: ahem! yes some of the rigs on the forum are superb but the power and the speed is getting past moped speeds now without any safety considerations, its a shame as it may be the difference between people getting hurt or killed with the effect of in some countries maybe e-bikes being banned totally, something we dont want of course.

Folks running brushed controllers should always fit them IMHO as controller failure (FET) will almost certainly result in a full throttle condition, most of the motorbikes on here do have them of course its just that there are quite a few e-bikes that are pushing similar speeds with no cutouts, I understand folks want to spend their dollars and time on making their bikes faster and go farther, however a 10 dollar switch might save your 2000 dollar investment and legal expenses, hospital fees, life etc.

Knoxie

 

[Jozzer]

Indeed, some method of killing power is essential. My motorbike has a contactor rigged to the killswitch, the KMX has a button on the bars that halfs voltage via a 40A relay, or a 50A manual switch handily reachable by my left bumcheek. The controllers powerswitch is right in front of me too, though I don't think I'd trust this in the event of fet failure. I've seen 2 brushless bikes go WOT on failure now...

you got that bike on the road yet Nick? About time you came over for a play in the workshop (you too Paul, if you can get a visa from the woman!)

 

[deecanio]

hehe,

hey guys whats up
funny you should post this as im an offender - however as if by magic i had already ordered this one last week, hasn't turned up yet!!
waiting on the 123's Steve, should arrive this week - then i'd like to drop by too ???

cheers


D
.............

 

[Malcolm]

a 50A manual switch handily reachable by my left bumcheek

I knew you southerners were odd Steve, but a prehensile arse was more than even I suspected :lol:

After hearing of Fechter's experiences wrestling with a runaway scoot I made sure I had multiple safetys:
Clutch lever connected to 250A breaker + killswitch that cuts power to contactor coil + inertia switch that cuts power to contactor coil in case I hit something or fall off...

 

[Miles]

I knew you southerners were odd Steve, but a prehensile arse was more than even I suspected :lol:

:lol:

 

[Jozzer]

Sure Deec, come down to party too!


Inertia switch Malc? Like a mercury type cutout? Nice idea, very sensible! Got a link to one?
Must get one too, I could hold it between my buttocks so the bike stops if I'm not the right way up (though it may hinder my ability to reach the bumswitch)

 

[Lock]

I'm interested in a "key" w/lanyard for my wrist or belt clip. Yank on lanyard, arm jerk, getting separated from the vehicle should all "pop" the key out (break contacts)... too low tech? Too inconvenient?
important thread
tks
loCK

 

[Malcolm]

Got a link to one?

I found a resettable mechanical switch from a Range Rover on ebay. You can usually find a few if you just do a search for inertia switch. It's a bit of an odd shape to grasp though

 

[Tiberius]

Good thread, important point.

One of the other things I drive is a hovercraft. On those, as also with jetskis I believe, we have lanyard between the driver and a cut off switch, so if the driver is thrown out, the engine is shut off.

As Lock says, could be useful on an ebike. But really you want a way of cutting the motor before coming separate from the bike. A lanyard could do that of course, if it was located somewhere easily reached.

Further thoughts:

How reliable are mechanical switches at opening with high currents? What about other ways, such as FET switching. Or how about a crowbar - where the e-stop switch shorts the main power line and forces the battery fuse to blow?

Why not combine this with a security feature? Ie, you have to put a special key / object / lanyard end into a socket to make it go, and can pull it out to stop?

Nick

 

[knoxie]

Hi Guys

Glad you are liking this one! it is a good point quite a lot of the rides on here dont run them, good to hear Deec is getting one as well, what ever way you do it its better than nothing, fet kill switches is a no no really as there is still a danger that the fet could blow short and you not realise, the safest method is really some kind of watchdog solenoid like Jozzer and Malc are using, so you have a fail safe is you like, 2 break contacts in series should one not work, we use a similar arrangement on the cranes to stop one crane bumping in to another using self monitored optical switches.

I dont think it is as important to kill the power if you leave the bike, its still worth doing I suppose on bigger bikes as you may fall off the bike and get pinned under it so yes why not on bigger rigs, its really scary if the bike takes off by itself, I have had it happen whilst stationary and the bike damn near broke my arm.

There are a lot of things you could do to make esp motorbikes safe, you can add in any number of serial safety switches, how many of you electric bikers run the solenoid circuit through the side stand switch? another cool feature and one that should be simple to replicate as all bikes are now shipped with the switches, you can have a wrist strap on the bars, how about a load sensor under the seat! there are lots of things you can do to make things safer.

Keep the pictures coming good to see all the other setups, Deec your switch looks like mine it was about 8 quid off fleabay, you could of course use this to energise a mechanical latching block on a small contactor, the contactor is held in by the block and released by the pulse from the kill switch, nice at you are not wasting power holding the coil shut, not the cheapest way of doing it and not man enough for a motorbike but should work ok for an ebike with a bit of pole wrapping!

Lots of ideas, be cool if for starters folks simply fit the kill button, no need for those brake lever things, you can hit the button quick enough, I regularly use mine to make sure my thumb knows just where it is, I did mount it a bit near my shifter once which caught me out! so its important to get it just in the right place, not to easy to accidentally hit it but near enough for you to reach it before you hit something or something hits you.

Knoxie

 

[Lock]

If I wasn't clear I am thinking that the "key" is like half a knife-switch. So the socket has two contacts + and - and the key just has a conductor in it that makes the connection. Breaking pack voltage, but I am only interested one HP around 20A only. Would need to be a water tight arrangement or a well sheltered socket when/where key is inserted.
Hopefully real KISS stuff. Part of my interest in a lanyard/key arrangement is for when the vehicle is being loaned out etc.
Possibly more effective than a BIG RED BUTTON, for newbies...
tks
Loc

 

[Tiberius]

Hmmm,

Two mode lanyard/key. My key runs it at full power, but anyone else's or the demo key is restricted.

Or for real dual mode in case it gets examined by the police, an RFID reader built into the saddle and I secrete the key somewhere on my person.

Nick

 

[deecanio]

Hi Paul,

yes mate, wised up eventually and ordered last week, i may even get a helmet too - im not sure i understand the method you say for hooking it up - was going to use the cables from my supplied brake levers and just connect the switch to the brake inhibit connector on my controller??? - having a temp stat in too that was going to use the same inhibit connector??
i haven't had any open throttle probs yet but i like the reassurance of the switch, just in case!!! - actually that said the two times ive lost control of the bike it's landed throttle side which is why im glad i dont have the full grip throttle anymore too!!


cheers

D

 

[mvadventure]

Good post, good responses and now I've gotta go put a kill switch on the bike. Having got caught in a nasty storm last year and having the throttle short out in the on position I should have done something sooner. Probably though I'll simply addd a little wire to the half ton already on the bike and move the key switch to either the handlebar or seat post where I can reach it.

Mike

 

[Eric G]

I do use the brake cutoff wires that come out of my c-lyte brushed controller to the front brake lever with a built in reed switch.

I do have a 20 amp toggle switch that I still haven't connected between the batteries and controller yet as an added cut off/on off switch.

Yes I believe safety is paramount!

Eric

 

[Link]

I have no kill switch because I don't need one. Since the batteries are in the backpack, the connection between it and the bike is very easy to sever if I need to. Though usually I have to push them back together rather than separate them because it wiggles loose and tries to go full throttle.

 

[Rassy]

When I added plug braking on my trailers, I installed a double throw toggle switch to allow the use of relays to connect/disconnet the motors to either the controller or the brake coil. So this gives me a built in kill switch.

The relays came from JC Whitney and are rated for 800 Watts at 12VDC:

http://www.jcwhitney.com/autoparts/Product/Pr-p_Product.CATENTRY_ID:2001332/c-10101/Nty-1/p-2001332/Ntx-mode+matchallpartial/N-10101/tf-Browse/s-10101/Ntk-AllTextSearchGroup?Ntt=800+watt+relay

The DC/DC converter to run the relays:

http://www.partsforscooters.com/s.nl/it.A/id.3243/.f

Now that I have the Watts Up meter I checked the current used by the converter and one relay. The converter in standby uses less than 0.02 Amps, and when the relay is activated, the total is less than 0.05 Amps.

 

[Pockets72488]

i have a e-brake handle that has been modified with a spring for return as it does not connect to a brake and use it like a clutch but i also split the wires to a SPST (Single Pole Single Throw) switch i can flip if needed however it is not needed as my bike does not have enuff power to kill me maybe hurt me a little as it has already (mostly operator error)

 

[mi7d1]

I use a knife switch that is remotely operated to disengage the batteries from the motor. I have had a stuck full on throttle lately. The kill switch has been installed since the day I built the system. One never know when it might be needed.

 

[ngocthach1130]

Hmm i thought about it and i was about to make a DIY version.

I would take a short section of a copper tube about half an inch long cut it so you have 2 C shape piece I will then break the positive wires on the battery connection and fit these 2 halves between then. By using a small copper cylinder I would make a make a connection similar to this (0). The cylinder will have a string or brake cable attached to it and leading up to the handle bar where it could be actuated by a thumb throttle of some kind. When the cable is pulled the cylinder will be pulled out of the 2 half and connection is broken.

I know, it sound retarded and would be easier to buy something like a switch but there's more fun in turning your bike into an experiment.

 

[Pockets72488]

I use a knife switch that is remotely operated to disengage the batteries from the motor. I have had a stuck full on throttle lately. The kill switch has been installed since the day I built the system. One never know when it might be needed.

yeah iv seen mi7d1's knife switch it's pretty cool, So how did the race go mi7d1? what did you place? i diddent get to go because we had a shipment come in and was supposed to be there at 9am but diddent show up till noon

 

[Deepkimchi]

Wouldn't the ebrakes perform the same function? You just have to hold them.

DK

 

[deecanio]

Hi DK,

i guess they would but as you say you would have to hold them in, trouble with the cutout levers for me is there only good for cable brakes also.

cheers

D