kill switch for handlebars - recommendation???

[callagga]

Hi,

Any recommendations re what to get for an e-bike kill switch I can buy? i.e. that will be rated for 20A at least. I've had a look in a local electronics store any there was nothing rated appropriately (I was looking at a toggle style switch). So sub-questions are:

- which type
- what brand / where to buy
- I assume you'd put it in series with the +ve power lead between battery and controller? (is this the best way to do it)
- any issues running the 36V (20A controller) wire from the pannier box up to the handlebars? just need a water proof kill switch perhaps?


tks

 

[mrgarci1]

I think the best solution here might be one of the brake levers with an integrated kill switch - if your controller supports it (I think most do), that's probably the safest, easiest, and most elegant solution. Just as an example:

http://www.e-bikekit.com/e-bike-kit.html

At the very bottom of the page, there's one listed for like $10. Not sure if there's a better place to buy one, or if it would be compatible with your controller.

Just my $.02

 

[callagga]

I was thinking of a kill-switch above and beyond the handbrake mechanisms - e.g. what happens if controller logic has a problem

Is there an issue running the 36V (20A controller) wire from the pannier box up to the handlebars?

 

[dogman dan]

Fuse holder with a string to yank on? Wire the on off switch on the controller to route though a hanledbar switch?

 

[callagga]

Wire the on off switch on the controller to route though a hanledbar switch?

I was wondering where to get an appropriately rated switch though - perhaps a motorbike shop?

 

[icecube57]

I have my Watts Up Meter on my handle bars. It has anderson connectors on it. The connectors have just enough tension to stay connected during normal operation. A nice gentle tug on one of them breaks the circuit and kills the power. Didnt have to spend anything.

 

[callagga]

not a bad idea - how do you weather-proof (eg bit of rain) the Anderson connectors?

 

[icecube57]

I suppose you could put silicone sealant in the back of the connectors. And or a dab of vasaline to prevent rust and corrosion on the contacts. The good thing about andersons is that everytime you connect and disconnect the connectors it cleans the contacts in the housing. If you solder them in it reduces you losses due to bad connectors. You can also adjust the tension on the anderson by taking a small flat head and prying up the contact just a hair if it seems to loose. This increases the contact pressure. Works great especially when you getting intermitten power drop outs or voltdrops or crackling and sizzling under load lol.

 

[callagga]

there's no safety hazard re having 36V exposed on the handlebars via the anderson connector (ie where they connect)? Or are the connectors reasonably weatherproof?

 

[callagga]

PS. As well as:

Q1 - Is there a safety hazard re having 36V exposed on the handlebars via the anderson connector (ie where they connect)? can I also ask

Q2 - I see a 12V 30A switch at the local electronics store - would this be OK a kill switch (in series with battery power to controller)? i.e. the Amp rating is enough but it is 12V not 36V? Here are the details (link & photo): http://www.dse.com.au/cgi-bin/dse.storefront/en/product/P7723

thanks

(edit) or perhaps this one is better (12 / 24 Volt, 100 Amp) - still doesn't say 36V?
http://www.bonzabuy.com.au/store/index.php?cPath=34_48

(edit2) or another interest one (Rated at 25 amps - suits 12 or 24 volt)
http://www.cassellmarine.com.au/p/576628/switch-pushpull-2-pos.html

 

[rhitee05]

A lower-voltage-rated switch would probably be okay the majority of the time. The trouble is it might arc if you try to disconnect it under heavy load - that's where the voltage rating comes in. Some switches are rated both DC and AC - usually with a higher VAC rating, which is because AC arcs are self-extinguishing when the voltage goes to zero mid-cycle. Unfortunately, this failure mode under heavy load is exactly when you'd most want your emergency disconnect to work reliably! Hopefully some of the other members with high-voltage setups will chime in to say what they use.

 

[XRuss]

Hi, I have been useing the key switch above (battery master isolator) for some time now on my WE BD36 sla 36v/12ah and it seems to be holding up well. I am now installing it into a small plastic box to mount under and facing forward of my saddle. It is then easily reached for a quick disconnect of the battery.



If you have a Harbor Freight near, they sell that switch, at present, for less than 5.00US.

A hell of a good deal.



When you turn it on, it has a really good snap to it. Must have a good spring inside so as to make a strong contact.



also found large hole lugs 12/10 gage to fit the large connections at Home Depot, small box of 8 for .99. Also a good price.



Good luck all. XRuss

 

[dogman dan]

My battery to controller wires are under the saddle, fairly dry as long as my ass is above it, and easy to reach if I need it. A yank on the andersons and A-OK. A switch to merely turn off the controller would only need to be as heavy duty as the one on the controller. Don't know if that would be enough in a runaway.

 

[zukster]

I just used a wall light switch that cost $1.50 at the dollar store. I siliconed it where the
wires screw on. Its rated at 15amps, not 20. I actually use it for the key switch ignition
wire, so I'm not surging the FETs with on/offs when I'm out and about. I'd feel okay
using it to switch the main power too, but I think using the key switch wire is better.

I was getting a lot of help on this when I set it up here

http://endless-sphere.com/forums/viewtopic.php?f=2&t=9407

Here's a picture. Under the seat means you don't have to run big wires to the handlebars.

 

[Joey]

It looks like you have the makings of an electric chair. Add 110VAC and you're good to go.

Joey

 

[zukster]

It looks like you have the makings of an electric chair. Add 110VAC and you're good to go.

Joey

Old picture. Plug is now changed to small waterproof one. Only using it for key power too - so no worries.

 

[MidniteTweeker]

I use the switch pictured above with the red plastic key on a 36V system. Works well. Switch seems very heavy duty & well built. $5 is an excellent price. Since my switch is difficult to reach, I also have a fuse with a tie wrap fastened round it to use as a pull in case of emergency.

MT

 

[zukster]

That looks like a good one. I think "The Source" carries it here in Canada.

Still - I'd like to get a waterproof one that has rubber over the button.

 

[XRuss]

The red key one is easy enought to waterproof. Just seal up the seams with silicone sealent. Put a rubber/plastic cap over the keyway when key is removed. It's a well made switch and should give good service. Cheep too.

 

[zukster]

I'll try that on my new project - "The Underwater Ebike!"

 

[callagga]

here you go zukster, a few options for you

[1] http://shop.voltelectronics.com.au/waterproof-toggle-switch-cover.html

[2] Join up with these guys who do waterproof switches - http://www.hydracon.com/