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THR-500-2 Compatible with SPD-SD400

I bought a THR-500-2 throttle and an SPD-SD400 controller. Can anyone confirm if these two are compatible?


I just finished my build (modified mobility scooter), and I'm not getting any output from the controller. 

One thing I failed to mention is that if there is a brake lever switch plugged into the controller then it needs to be unplugged during the test because if the brake lever switch is faulty and continually in the closed position then the controller will not operate. A properly operating brake lever switch is normally open so the controller needs to read open brake switch wires to run the motor. 

If the motor has been tested and runs directly off of the battery pack, the brake lever switch is unplugged from the controller, and the battery pack Voltage was checked during the test and held above 22 Volts then that is the only test needed for the controller.

Looking back at your test results both the controller and throttle are showing signs of unusual terminal Voltages and behaviors. If you could please contact our customer service department and request warranty service on the controller and throttle then we can test these parts together to determine if one or both of them need to be replaced.

Please submit your warranty service request using the contact form at this link and someone will reply back to you right away: https://support.electricscooterparts.com/support/tickets/new

Please let us know if you have any questions.
Reading back on your last reply I noticed that there is 22V between battery ground and the controller's positive motor output wire. The controller's battery pack input positive wire runs directly to the motor's positive output wire without going through any electronics as the controller pulses the motor's negative wires since it uses MOSFET transistors.

If you are getting 22 Volts between battery ground and the controller's positive motor output wire then that should be the Voltage of the battery pack. Just food for thought here. We would need to the controller and throttle in our shop for testing to be 100% certain exactly what the problem is.
Thanks. I opened a ticket to request the warranty service, as suggested. The battery pack was still reading above 25V when I tested the motor outputs. So I expect something is wrong. Thanks for the insight into how the MOSFET drivers work in the controller. Interesting stuff.

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