Saturday, May 28, 2011

How to fix a broken Hill Topper SLA Kit

It was June 3 last year (2010) when I got my Hill Topper SLA Kit. It broke down last April 27, 2011, after 10 months and 60 recharge cycles.
What happened is that a day before it broke down, I noticed that the chrome plug connected to the battery became very hot after a 1 km long steep climb. I was still able to use it the following day but suddenly the motor stopped turning. Since it was the end of my everyday 9 km bike to work, I thought that the battery was just drained as usual. So I just charged the battery while at work. When I was on my way home facing my usual 1 km steep climbs, the motor went totally dead. Imagine climbing a 1-km long steep stretch without motor assist and 3 kilos of battery to carry. That ordeal made my legs strong enough to bike the next 18 days with an average of 3 kms steep climbs per day without my Hill Topper.

I contacted Clean Republic on May 3 about my SLA kit problem and they responded on May 7 suspecting that my SLA battery pack's controller fuse was the problem. Clean Republic sent me a new controller on May 10 with an upgraded fuse system (for free) as part of my 1-year warranty. My new controller was delivered to me by post on May 20, 2011 and I started working on my battery pack that night.

When I tested the battery pack with the new controller, the motor still did not work. I reported back to Clean Republic on May 22 and got a reply on May 25 asking to confirm if the battery is charging. On the same day, I replied with a confirmation that the battery is charging and then sent a follow up email on May 28.

While waiting for a reply, I began to worry that my Hill Topper could be dead forever. Since I was becoming desperate, I tried to give my kit one last chance before giving up. This time, I suspected that some wires must have melted inside the female chrome plug connector (recalling that that plug became 'very hot' the day the motor stopped turning) and that the design of that plug makes it susceptible to stretching the wire soldering inside every time it is pulled out when recharging the battery. When I started to open the female chrome plug I noticed that it was loosely screwed and that the yellow wire is detached and the blue wire is barely hanging. The green wire broke off as I exposed the wiring. It was then that I realized that
the REAL problem that caused my motor to stop turning (despite a fully charged battery) was the disconnected wires inside the female chrome plug. The yellow and blue wires might have even shorted as a result of the constant pulling off of that plug when disconnecting the battery pack for recharging. I think this chrome plug connection needs to be redesigned to avoid the tendency to get the wires pulled off their soldering to the pins inside.

After soldering back the disconnected wires (and accidentally searing two of my fingers slightly with the soldering iron) and after reinforcing the cable connected to the female chrome plug, I connected my battery pack and turned on the motor. Lo and behold, my Hill Topper motor started to work again!

To help other Hill Topper users who might be experiencing the same problem, I hereby share what I learned from trying to fix my Hill Topper. You could probably fix your Hill Topper problem yourself too!

HOW I FIXED MY BROKEN HILL TOPPER SLA KIT

Problem: Motor not turning despite fully charged battery (charger LED turned solid green after charging).
Symptoms: Loose female chrome plug parts, with episodes of chrome plug becoming very hot when engaging the motor.
Solution: Re-solder disconnected wires inside the female chrome plug and reinforce the cable insulation with electric tape to prevent stress to the wires when pulling it off for recharging. Be sure that none of the plug parts are loosely connected (especially the black plastic housing the 7 holes: make sure that this is tightly screwed unto to the chrome part).

Steps:
1. Remove the two tiny screws that attach the small clamp to the female chrome plug.
2. Twist the black plastic tip (with 7 holes) off from the chrome part of the plug to remove it and expose the wires inside that are connected to the 7 pins on that plastic tip.
3. Be sure that the following color-code wires are securely soldered to the 7 pins. If not, solder them back in place using a soldering iron:
MOTOR-CABLE FEMALE CHROME PLUG CONNECTIONS
1 none
2 none
3 YELLOW
4 BLUE
5 GREEN
6 BLACK
7 RED
ON THE OPPOSITE END OF THE MOTOR-CABLE THE BLACK (pin 6) and RED (pin 7) WIRES ARE CONNECTED TO THE SWITCH, SO BY DEDUCTION, THE YELLOW, BLUE, and GREEN WIRES MUST BE CONNECTED TO THE MOTOR BATTERY PACK-CABLE MALE CHROME PLUG
1 FAT RED
2 FAT BLACK
3 YELLOW
4 BLUE
5 GREEN
6 ORANGE
7 THIN RED
ON THE OPPOSITE END OF THE BATTERY PACK-CABLE THE YELLOW, BLUE, GREEN, ORANGE; THIN RED WIRES ARE CONNECTED TO THE CONTROLLER,


Controller wiring diagram (source: CR Forum)


THE
FAT RED; FAT BLACK WIRES ARE CONNECTED TO THE BATTERY, A PALE RED WIRE AND A FAT RED WIRE ARE STICKING OUT OF THE CONTROLLER AND ARE CONNECTED TO THE BATTERY

4. Put back the black plastic tip back to the chrome part of the plug and screw back the clamp to secure the cable.
5. Reinforce the plug attachments by putting electric tape around where the clamp with two screws are and the cable attached to the plug.
6. Connect cable to battery pack and turn on the switch. Your motor should start working again if the wires are correctly reconnected.

SLA battery pack wiring diagram (source: CR Forum)

Here is a picture of my SLA kit unpacked:


IF AND ONLY WHEN YOUR MOTOR STILL WON´T TURN ON, PROCEED TO STEP 7


7. If the fuse/s inside the controller is busted, the motor will still not work despite the wires inside the plug being securely and correctly connected. You need to replace the controller with a new one ONLY in this case.

To replace the controller, open the battery pack by removing the battery and controller inside the black nylon bag. Remove the cloth tapes from the battery and the controller to expose the wires. Take a picture of the original connections for reference before cutting off the old controller for replacement. When connecting the new controller, be sure the wires are soldered correctly to the right connections as indicated in the picture (on the right, above). Be careful not to short circuit any wires of the battery to avoid fire. The black and red wires between the switch and the battery could easily burn if the battery is shorted. In the picture (on the right, above) you will see that the wires are color-coded and the black wire connected to the controller and the second battery is connected to the pin on the side of the switch where the LED indicator is (the ´on´ side). I placed a white electric tape on that black wire to distinguish it from the other black wire and to remind myself that that one with the white tape is supposed to be connected to the pin under where the LED indicator is and not on the other pin under which the switch is turned off.
The single red wire connected to the second battery should be connected to the
middle pin of the switch (I placed green tape on this red wire as reminder) and the single black wire connected to the other battery must be connected to the opposite pin on the switch (under the ´off´ side). Connecting the two black wires to the wrong pins will short circuit the battery and will cause the wire insulation to burn up like fireworks. SO BE CAREFUL!

If everything has been fixed (either by re-soldering disconnected wires or replacing the controller or both), your motor should now turn on when the throttle is engaged as usual. Put back the cloth tapes on the battery and controller and put these inside the black nylon bag. You may need to sew back the nylon bag to cover and protect the sensitive wirings inside from the elements.

The above solution worked for me and I hope others will find it useful as well.

NOTE: More posts on e-bike conversion projects are available here