Hall effect brake switches

[benjy_a]

I want to add brake stop switches to my Ezee hybrid conversion (hydraulic brakes). The issue is that the 2012 Ezee kit has 3 wire hall effect switches rather than the usual simple 2 wire on/off switches.

Is there any way to wire up a simple on/off switch to the controller to make it work? I want to use a hydraulic switch but the one I have found is a simple normally open switch which is closed under pressure.

 

[JuicyBike]

Hi Ben
You can use the 5V power from the controller to power the switch, definitely NOT the 36V. The other two wires simply connect to the normal brake cut-out connectors at the controller.

You should be able to safely experiment so long as you use the 5V supply. 36V will fry the transistor.

 

[benjy_a]

Thanks for this.... I'm still not sure exactly how the switches work.

Where does the switch normally get 5v? Through one of the 3 wires going to it?

I have measured the resistance across all 3 wires coming from the switch and no combination has zero resistance with the switch either open or closed. Am I being dense?

 

[flecc]

One wire is negative, one is the positive 5 volts, both from the controller, and the remaining one is the signal to the controller. Generally the positive and negative are the usual red and black colours respectively, the third colour (often yellow or green) the signal.

The sensor is a bit like a transistor, not a resistance device. It passes the 5 volts to the signal wire as the magnetic field changes across it. These are simple on/off types for brake switches, the ones in throttles are progressive, changing the signal level according to magnetic field strength.
.

 

[benjy_a]

Thanks Flecc...so can I just connect the positive to the signal wire to activate the cutout and ignore the negative wire?

 

[PJM]

I removed the sensors from the brake levers that came with the kit. I then shaved off the plastic moulding to make it flat all around. I stuck this to the hydraulic brakes. I then used the magnets from the cyclezee brakes and used a piece of coat hanger wire to make a small attachment to the lever on the hydraulic brakes to increase the throw. With a bit of gentle bending I managed to get magnets to make contact with the sensors and cut the power. The sensors that come with it are normally closed and the magnet 'opens' the circuit. I have purchased a pair of normally open reed sensors and plan to make a tidier fit at some stage but whilst it works I am not going to bother. I used high strength 3M double sided to attach the centre to lever body. I wrapped the 'lever' add on and magnet in self sealing tape and fixed it to the lever by clipping it in to the hollow section and securing with a small cable tie. It is almost invisible. This way no messing with any wiring and it just works.

 

[flecc]

Thanks Flecc...so can I just connect the positive to the signal wire to activate the cutout and ignore the negative wire?

It seems from what PJM says that you need no signal for the motor to run. However, if that cuts it, yes, just feed the 5 volts back down the signal wire.

 

[PJM]

My reed switches only have two wires. However if you can adapt the switches without cutting any wires it will not be an issue. I assume you have the mk 2 kit as mine is the mk 1.

 

[Deleted member 4366]

The way I understand it, the signal wire from the hall brake switches go high (5v) when you apply the brake. Some controllers have a special (normally single wire) connector for this type of brake switch. I believe that you can connect these switches to the normal brake switch connectors because they're looking for a low (0v) signal - unless someone can tell me otherwise.

 

[benjy_a]

I made a mistake. I only tested one of the brake switches for resistance between the pins and got nothing, therefore assumed these are hall effect which was then confirmed by Cyclezee.

However, I can now confirm that both of us were wrong and the MK2 kit has simple switches. I tested the other brake lever and found that only two of the pins in the (3 pin) connector are used and it is a stadard NC micro switch. The first lever I tested is faulty which led me down the wrong path!

So....back to plan A for me and I'm ordering a hydraulic pressure switch.

Good to know a bit more about hall effect switches anyway!

 

[flecc]

Glad that's sorted Benjy, obviously eZee haven't changed the switch type from what they've previously used.