Reed Switch buggered

[Kingfish]

Arrrg! Yesterday I extracted the reed switch and magnet from another e-brake lever that was lower in quality, and I was moving it to the Shimano that I planned to use. Using Gorilla Glue, I placed the reed switch on the side of the brake and I thought that I had gently clamped it down for overnight. Today though the switch is acting really funky and more like flakey; I think I clamped it too hard and now it will have to be replaced

Need a bit of help here:
I know it’s 5V low current (150ma?), but the part I am confused about is whether it would be SPST-NO or would it be –NC? I know the difference between the two switches, and I figure that it's -normally opened, yes. It’s just that is normally With or Without Magnet? Know what I mean Vern?

Next question, who makes a good replacement? Digikey, Mouser? Any recommendations? I’m seeing the prices float between $3 at Radio Shack to >$28. I don’t want to sell a kidney for a gold-plated what’s-it’s.

Thanks in advance.
~Clumsy

[Kingfish]

Fixed the problem.
Instead of replacing the reed switch I went back to the drawing board and tried another way of mounting the magnet to get the switch to work.

Do I think the reed switch is broken?
Yes; it is not as sensitive over the entire length as it was before my attempt to mount the unit, however it is still useable at both ends. I changed the physical orientation of the magnet which brought it into closer proximity with the active elements within the switch and that has resolved the problem two-fold: I have a working switch, and it is quite sensitive to distance ~ better than I had planned.

I got the idea to mount the magnet differently when I had to spec the part on Digikey; there’s a proximity rating for these devices, and one of the choices is how far away does the magnet have to be to activate/deactivate…

This is the third time I have tried to mount this blasted magnet; worked like a charm.


I tipped the magnet on its’ side and super-glued it onto the handle.


To protect it from getting knocked off, I applied a healthy dab of clear RTV silicone.
After curing overnight I trimmed it up a bit with a sharp box cutter to get the desired shape.


Looks nice and tidy when closed; hardly notice it's there...

Sensitivity: 4mm, quite repeatable, slightly more than enough to take up slack; good enough.

Cost of repair: The price of the superglue and the RTV, which amounted to less than the price of the replacement reed switch. It’s kinda ghetto. Maybe the silicone will clear up more.

[jateureka]

If talking about the complete e-brake lever assembly then it has normally open contacts. BUT
If talking about just the momentary push button switch in that assembly then it has normally closed contacts, as in when you pull the brake lever in the switch springs out to its normal position. This also applies to the reed switch pulled away from the magnet it is in its normal position and has closed contacts.

More on reed switches in the tech ref section here http://endless-sphere.com/forums/viewtopic.php?f=16&t=11760

If your motor is not working You can test this brake switch by disconnecting it from the controller, if your motor now works then the brake switch is faulty.

[Edit: the first 2 comments are with regards to most Chinese brake levers and controllers that I have dealt with]

One exception is the Aprilia Enjoy which uses normally open switches (normally closed brake lever assemblies).

[Kingfish]

Jateureka,
Thank you for the insights … and the proverbial kick in the rump to square up my thinking
I’m back to buggered with the brake

This ebrake is for my other bike that does not yet have the motors mounted. However I took my current bike (P0) and used that to test.

• Attaching the multimeter to P0’s momentary switch (my ghetto ebrake) I noted that the switch is NO, and pressing the button makes contact (short). We know this setup works.
• I parked P0 next to P1, attached the recently modified ebrake to P0’s controller, lifted the front wheel and gave throttle: Nothing. I opened the ebrake, engaged throttle – and the wheel spun: Wiring is backwards on the modified ebrake.

Multimeter test:

Brake in “normal” position, ebrake shorted.


Brake in “braking” position, ebrake opened.

I examined closely the original ebrake.


The green shaded area denotes where the magnet used to be. I cannot fathom how this arraignment is any different than what I assembled on the Shimano brake. This ebrake came from ebikes.ca.

Checking my order, the p/n was eZeeEbrake, at the time this was the only ebrake lever offered (December 2009).


Here's the unit on the ebikes website.

Do you see anything here denoting that it is NO or NC?

If you browse the site today there are two more types of ebrakes offered:

LEFT... (the image is mismarked)


RIGHT.

Both are NO.

I was buggered before I started; the item that they sold me would have never worked with my controllers

Jateureka,
Thanks for helping me get back on the right path; I really appreciate it.
~KF

[amberwolf]

I just a couple of days ago had to deal with making a way to engage the brakes on my Lyen controller, which operates in a different way from my Fusin. The Fusin uses a hall ebrake, which outputs ~5V when engaged. But the Lyen expects a *ground*, 0V signal, to engage the brake.

Worse, I already had a relay setup to be turned on by the 5V from the hall ebrake, to turn on my brake lights. So I changed to a 12V relay that is now operated by a switch providing a ground to it's coil, other side of which is powered by 12V from the lighting system. The relay has two poles so one switches the brake light by providing 12V to it, and the other provides a ground to the ebrake signal line.

The switch itself, rather than dealing with yet another thing on my handlebars (or something else I can break off my brake levers, as I have managed a few times before), went on the brake arm area at the fork instead.

There are details in my DayGlo Avenger thread on page 7 or 8.

It was kind of annoying to have to come up with another way to do it; for some reason I had assumed that pretty much all ebike controllers nowadays used the hall type ebrake levers with a 5V output, but that was pretty silly of me. After actually researching it, it seems more a 50/50 kind of thing. Oh, well, at least now I have yet one more trick to deal with the issue if I run into it again.

[mwkeefer]

If it helps, I use hall sensors and never have issues... Powered from throttle 5v and gnd then inverted with a little transistor. 2 parts - solid state and no issue with vibration + add a cap and resistor and tune the trigger sensitivity!

Mine us just hotwired together ugly as he'll but highly reliable and cheap!

Hope it helps!
Mike

[Kingfish]

AW/Mike –

Last night I did a lot of digging to find a replacement reed switch; came across this manufacturer that has some really well presented information here: How a reed switch works

After viewing, I wanted to pause and sleep on what I had learned. Then looking for something else to work on last night, I tore into my throttle to make it a 2-channel HE for 2WD (ref: 20KW 2WD having misfires).

This had me thinking about a recent thread on variable regen braking: Modifying a Hall Brake lever for Variable Regen Braking

I’m already constructing a 2WD and this would be a good place to separate yet another signal cleanly. The choice is whether to do this as:

1. 2-Channel Magnetic Reed Switch, or
2. 2-Channel Hall Effect with (relative) linear feedback.

One fly in the ointment is the recent change in the controllers from ebikes.ca:
How do you configure the Infineon controller for Regen?

P0 has controllers from pre-Feb 2010, and I bought two more after that with the newer mod for use on P1. However, I do not have data on whether the engage-regen/roll-throttle for more regen effect works with these newer units. I LIKE the control that I have with initial regen drag and rolling the throttle forward for more; this completely saves my brake pads as I dial in to a precise coast/stop. I wonder aloud if this “feature” has gone missing. Unfortunately I won’t be able to test this for at least another two weeks.

Q: Is anyone using the 6FET controllers post-February with Regen?

Guys, thanks for the optimism
~KF

[GrayKard]

After viewing, I wanted to pause and sleep on what I had learned. Then looking for something else to work on last night, I tore into my throttle to make it a 2-channel HE for 2WD (ref: 20KW 2WD having misfires).

This had me thinking about a recent thread on variable regen braking: Modifying a Hall Brake lever for Variable Regen Braking

I’m already constructing a 2WD and this would be a good place to separate yet another signal cleanly. The choice is whether to do this as:

1. 2-Channel Magnetic Reed Switch, or
2. 2-Channel Hall Effect with (relative) linear feedback.

If you do go with the dual Hall throttle then take a look at this thread: Improving Throttle Response with Headline BLDC Controllers

It has some good info on how to get the Hall sensor that is further away from the magnet back into the proper voltage range. I need to do this with my throttle as the new controllers I'm using now aren't as forgiving as the old ones as far as voltage thresholds.

Gary

[amberwolf]

If it helps, I use hall sensors and never have issues... Powered from throttle 5v and gnd then inverted with a little transistor. 2 parts - solid state and no issue with vibration + add a cap and resistor and tune the trigger sensitivity!

I considered this, but I would have had to cut into the throttle cable or open the throttle up to get 5V up there, and I am trying to leave all of the new bits as totally intact as possible so they stay purty, unlike everything else I have.

The other alternate of inserting a tap connector on the throttle at the controller doesn't appeal to me, because I think my wire bundle now is already somewhere around the thickness of a typical 10-speed's top tube.


@Kingfish: My 6-FET is from Lyen, and if it has that option I don't think it's setup that way, as I was trying to verify operation of the ebrake, that it disables the controller, and so moving the throttle after engaging the brake/regen does not appear to alter teh amount of regen.

[jateureka]

If the brakes worked with that controller before you removed and remounted the switch and magnet then one other possibility is that the brakes are not actually using reed switches but are using hall sensors as switches. Some hall sensor switches are polarity sensitive in that you have to mount the magnet with either N or S facing the switch to get the desired output.

[Kingfish]

If the brakes worked with that controller before you removed and remounted the switch and magnet then one other possibility is that the brakes are not actually using reed switches but are using hall sensors as switches. Some hall sensor switches are polarity sensitive in that you have to mount the magnet with either N or S facing the switch to get the desired output.

Actually I had never used that ebrake before; it was part of the original order and a component that had not been used before. The description says it is a reed switch. Although I am with you on the polarity; I understand that it can make a difference, but in this case ~ not enough to change it from NO or NC