Author Topic: Magic Pie Edge PAS hookup.  (Read 2211 times)

Offline Thingamajig

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Magic Pie Edge PAS hookup.
« on: September 27, 2021, 01:49:05 AM »
Hi all.

So I've got a Magic Pie edge, and a pedal sensor which is a large bulky 5 magnet type as pictured in link


https://imgur.com/a/HgkYU5Y

(Second picture down)

I'd like to replace it with the 12 magnet, compact PAS sensor though as shown, first upper pic.

So here's my questions

1. I'm able to solder, so can I just wire up the smaller one without any compatability issues/risk? (Both have 3 wires so I think functionally they're identical?)

2. If yes to 1, What wires does the PAS hook up to on the controller? ( I've yet to get this build going)

3. What options or settings do I need to enable to make the PAS work? (Software wise)


Hugely appreciate any assistance. Thank you very much.



Offline Bikemad

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Re: Magic Pie Edge PAS hookup.
« Reply #1 on: October 05, 2021, 04:06:13 PM »
Hi andto the forum.

Unfortunately, there are different types of 3 wire PAS sensors and not all of them are compatible with the Magic Pie controller.
Some have a variable analogue voltage output and other use pulses to determine the speed and direction of the pedals.
The correct three wire pulse type PAS sensor must be used with the Magic Pie, unless you are using a Cycle Analyst unit combined with a separate torque sensor to control the Magic Pie's throttle input.

More information on PAS sensors can be found here.

The PAS sensor wires connect to the unterminated Red, Black and Yellow wires on the motor harness:





The PAS is typically enabled by default, but you may want to alter the PAS Ratio setting to adjust the default level of assistance to suit your preferred pedal rpm.

Alan
 

Offline Thingamajig

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Re: Magic Pie Edge PAS hookup.
« Reply #2 on: October 05, 2021, 04:35:22 PM »
Hi andto the forum.

Unfortunately, there are different types of 3 wire PAS sensors and not all of them are compatible with the Magic Pie controller.
Some have a variable analogue voltage output and other use pulses to determine the speed and direction of the pedals.
The correct three wire pulse type PAS sensor must be used with the Magic Pie, unless you are using a Cycle Analyst unit combined with a separate torque sensor to control the Magic Pie's throttle input.

More information on PAS sensors can be found here.

The PAS sensor wires connect to the unterminated Red, Black and Yellow wires on the motor harness:





The PAS is typically enabled by default, but you may want to alter the PAS Ratio setting to adjust the default level of assistance to suit your preferred pedal rpm.

Alan

Thanks for the reply - funny that you do it today because I just uncovered a previous post of yours where you stated the same thing:

Hi Jeff andto the forum.

If your existing PAS sensor is a variable voltage type it will not work with the Magic Pie Edge, because the controller (and Smart Display PAS levels) is designed to work with a pulse type PAS sensor.

Both types of sensors use three wires, but one produces a variable voltage in relation to the pedal speed, while the other produces a series of pulses that also vary with pedal speed.

Fitting the correct PAS Sensor should hopefully enable the Pedelec to work as intended.

Alan



I presume that most PAS sensors on the market today are all the "Variable" voltage type and not the Pulse type you mention?

Is there a way to determine what type it is with some creative use of a multimeter? (Thinking about hooking it up to one and using a drill or something to try different rotational speeds and see what reading I get)

Finally; if I do wire this up (Assuming, all correctly) is there any risk of damaging the controller? From what I understand the 5v regulator in these controllers are quite fragile and I don't want to wind up causing permanent damage to them.

thanks again for your help, much appreciated.

Offline Bikemad

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Re: Magic Pie Edge PAS hookup.
« Reply #3 on: October 05, 2021, 05:00:48 PM »
I presume that most PAS sensors on the market today are all the "Variable" voltage type and not the Pulse type you mention?

Is there a way to determine what type it is with some creative use of a multimeter? (Thinking about hooking it up to one and using a drill or something to try different rotational speeds and see what reading I get)

Finally; if I do wire this up (Assuming, all correctly) is there any risk of damaging the controller? From what I understand the 5v regulator in these controllers are quite fragile and I don't want to wind up causing permanent damage to them.

I think the majority of PAS sensors utilise the pulse system, but there is more than one type of pulse system.

I don't know whether a voltmeter would be able to determine which type of pulses were being produced but it should be able to show a voltage variation in relation to rpm for an analogue voltage type.

I simply mounted the magnet ring in a drill using a nut and bolt when I initially tested my PAS system over 10 years ago, but it enabled me to check the working direction (and the working distance between the magnet ring and the sensor unit) before fitting the unit to my bike.

I don't think that you would be able to cause any damage to the controller unless you somehow manage to short the +5V supply directly to Ground.  ::)

Alan
 

Offline Thingamajig

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Re: Magic Pie Edge PAS hookup.
« Reply #4 on: October 06, 2021, 01:56:17 PM »
Righto. Thanks very much for the help Alan, is hugely appreciated.

I will attempt to use the desired PAS sensor but if no joy i'll use the one that came with the kit. Will inform how it goes with a reply.

Again, many thanks