SW900 how to find correct setting for P17 Power choice

[jimmychill]

dumb newbie move here, but I was poking around in the SW900 that came with my ebike, and I think I changed too many settings, and now it's not functioning properly. The setting I need help with are P07 (Magnets quantity to measure speed: 1-100), P13 (Power assistance magnet quantity setting: 5, 8, 12), and P17 (Power choice function: 100-200). How do I find out the correct values for these settings?

I have a Cyrusher XF700, 250W motor: QH4GV 36V*250 W Brushless Hub Motor

 

[vfr400]

P07 is normally 1 but can be 6. you can see from the speed display which is right. For P13, you have to look at your pedal sensor magnet disc (if you have one) and count them. If you have the type of sensor that clips into the bottom bracket, it's 12. P17 sets the current, but i don't know the relationship between the number and the amps, so set it to 100 and see how you get on. if it's not enough power, turn it up. How far you go depends on your battery. If you go too far, your battery will start cutting out. I can only guess that around 130 might be a nice compromise between power, range, heat and battery life. That's if 100 relates to the normal 15 amps or 600W maximum.

If you have watts on the LCD, you can set it to up to 800w without much chance of problems. You only get maximum power at low speed, so to test, set to level 5 or whatever is the maximum, pedal along in a low gear and use the brake to hold the speed to about 4 mph for a short time while you read the power on the LCD.

 

[jimmychill]

vfr: thank you. That may be just what I'm looking for.

P07: I've read that for a direct drive motor it should be set to 47. I'll try that later today, and then maybe try 1 to see what works best.
P13: I counted the magnets and I have 5, so I can use that setting.
P17: I'll try 100 and see how that goes. Thanks for the explanation of what it adjusts. the user manuals on these things are anemic at best.
Interesting point on the test.

Thanks again for the help.

 

[jimmychill]

Following up on this. Setting P07 to 1 works well. Thanks again, you've been a big help!