Lectric XP Lite - Choosing Generic After Market Controller

Company: Lectric
Model: XP Lite 1, 1st generation
Part: Microcontroller
Display Protocol: UAT2
Motor Hub Power (max): 350W
Microcontroller Power (max): 350W

Overview

Microcontroller, or the e-bike forum called as controller, is one of the part that commonly failed.  Replacing it with original Lectric controller will be 2x - 5x the cost compare with aftermarket part.  This post explains how to choose the aftermarket controller, with several options

Many of the controllers have following standard connectors for electric bicycle, which exists for Lectric controller as well:

1. Motor's phase wire - 3 power wires, which are thick
2. Motor's magnetic hall sensor - 5-wires 2 for 5V supply, 3 from each of the hall sensor
3. Battery power - 2-wire power input into the microcontroller board, e.g. 38V, 48V, 52V, 60V, etc
4. Brake - 2 pair of 2-wire brake sensing wire, which will disconnect power to the motor when braking
5. Pedal's power assist (PAS)- 3-wire to power the motor when pedaling
6. LCD display - 5-wire for Lectric bike. It is using UAT2 protocol, which is the display used for all hub drive electric bicycle (not for newer generation mid-drive bicycle)
7. Throttle - 3-wire.  Internally, it is a potential meter control with 5V supply

Following are the specific, but optional for Lectric bicycle:

1. Front light - 2-wire power to the front light. Light is controlled from the LCD display
2. Rear light - 2-wire power to the rear light. Same as above. This wire is soldered in parallel inside the controller, so it switches on/off together with above.  No separate control for the rear light
3. Speed sensor - 1 wire.  This wire is input from the hub motor.  Most electric bicycle does not has this wire, but all mid-drive motor requires this wire

Following does not exists in Lectric bicycle's controller (I'm referring to microcontroller's feature):

1. Hub direction control - 2-wire connector to toggle the direction of where the hub turn
2. Reverse function - to reverse the bicycle. Commonly used for heavier model, but common for fully size electric scooter/bike
3. Horn
4. Turn signal light
5. LCD display lock
6. Motor lock - basically disconnecting the power wire to the controller to allow to install an additional key-turning-switch

Purchase Options

Due to the Lectric bicycle specific connector below, there are several options you can choose:

1. Front light - 2-wire power to the front light. Light is controlled from the LCD display
2. Rear light - 2-wire power to the rear light. Same as above. This wire is soldered in parallel inside the controller, so it switches on/off together with above.  No separate control for the rear light.  So if the aftermarket does not has dedicated connector for it, you can connect this to the same connector as front light
3. Speed sensor - 1 wire.  This wire is input from the hub motor.  Most electric bicycle does not has this wire, but all mid-drive motor requires this wire. The LCD screen still able to show the speed even this wire is not connected. So this connector  is optional

Follow are the 3 options, which offers you different price point than 

1. 100% match of Lectric controller - this will be the most expansive aftermarket controller.  There will be a little different in the connector which you might need to swap. So prepare for soldering, cutting, crimping (if you prefer cosmetic)
2. 90% match without speed sensor - 90% of the controller does not need dedicated speed sensor. This controller offers 1 connector to power 1 light.  This will be the 2nd easiest to find, and cheaper than above. Price is ~CAD$30 
3. 80% match without speed sensor, and light - Missing additional head light connector. This is the cheapest, and cheapest to find. Price is CAD$10-20

In terms of controller's power rating, this model comes with 350W controller. XP Lite's body can only install controller with ~ 12cm long or ~ 4.5".  As of writing of this post, this limit to 500W max microcontroller. Newer XP Lite 2 uses 500W, while XP3, XP4 has longer body to allow to fit 1000W controller.