Adding a speed limit switch to a Sabvoton 72150

Hey all,

Im looking to add a speed limit switch to my bike which uses a Sabvoton 72150, it unfortunately does not have a 3 speed connector or speed limit connector. I can change the motor power limit using the MQCON configurator and using the internal set option. In order to hook up a physical switch to change this on the fly without reprogramming the controller, what pad can I hook this up to? I am also assuming that when the circuit for the switch is open it will not be limited and when there is resistance it will activate the set power limit.

Please note that I am using PAS so I cannot use a three speed switch and I only want to limit between slow speed and max speed. I have also found a thread which documents the internal pinout of the PCB but the external speed limit switch was not documented.

I appreciate any help, apologies for any gramatical mistakes but english is not my first language. Thanks!

I have a dead 7280 with a 3 speed switch apart on my bench right now. The relevant wires are clear, pink and black/ ground. The clear and pink wires go to the pads closest to j23 and j7, respectively. I'm pretty sure you short the pink wire to ground to get the low speed limit, and ground the clear wire for high speed. An open switch gets you the mid speed limit, which you could set to full power if you only want to use 2 settings. I don't know that the pad numbers will be the same on your 72150 and there's certainly a chance I have the 2 wire colors backwards, I can't verify anything on this one.

bengxe said:

I have a dead 7280 with a 3 speed switch apart on my bench right now. The relevant wires are clear, pink and black/ ground. The clear and pink wires go to the pads closest to j23 and j7, respectively. I'm pretty sure you short the pink wire to ground to get the low speed limit, and ground the clear wire for high speed. An open switch gets you the mid speed limit, which you could set to full power if you only want to use 2 settings. I don't know that the pad numbers will be the same on your 72150 and there's certainly a chance I have the 2 wire colors backwards, I can't verify anything on this one.

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I can confirm that someone else showed J7 Pin 6 as the high limit wire (Pink) and J23 Pin 1 as the low speed limit wire (Clear).

If anyone knows what pad the external speed limit wire connects to sharing it would be greatly appreciated.

⠀⠀⠀ said:

If anyone knows what pad the external speed limit wire connects to sharing it would be greatly appreciated.

Click to expand...

If you're referring to the ground wire for the switch, mine goes to an unlabeled pad with 2 other ground wires on the corner of the board. You can actually sort of see it in my picture above, its the black wire on the far right. But it can also go anywhere you have B-.