Search found 24 matches

by tstephens
Sep 16 2014 10:53am
Forum: E-Bike General Discussion
Topic: EM3EV charger switch voltage?
Replies: 26
Views: 3178

Re: EM3EV charger switch voltage?

bono wrote:Problem solved... The charger needs to be switched to 110V.
I had the same problem with mine when I received it. I caught it before charging though. I would recommend that everyone check this switch before powering it on.
by tstephens
Sep 12 2014 12:45pm
Forum: E-Bike General Discussion
Topic: EM3EV charger switch voltage?
Replies: 26
Views: 3178

Re: EM3EV charger switch voltage?

Unfortunately you will need to provide us with more information before we can help you out. How many volts was the battery after charging? How many volts was the battery after the ride? You will need a multimeter to measure the # of volts.

-Tim
by tstephens
Jul 31 2014 12:14pm
Forum: E-Bike Technical
Topic: controller screw size -- lost my screws
Replies: 4
Views: 400

Re: controller screw size -- lost my screws

I picked up some #4 x 3/8" pan head phillips sheet metal screws at Home Depot. They fit perfectly.
by tstephens
Jul 28 2014 10:59am
Forum: E-Bike General Discussion
Topic: HELP!! Tried to connect battery and it sparks
Replies: 19
Views: 2749

Re: HELP!! Tried to connect battery and it sparks

Did you plug in the pre-charge tail last? The tail has a pre-charge resistor in it that will prevent the flash from occurring. It the tail is plugged in last, then the spark should be avoided or at least minimized.
Pre-charge Tail2-500x500.jpg
Pre-charge Tail2-500x500.jpg (84.74 KiB) Viewed 2662 times
by tstephens
Jul 25 2014 12:33pm
Forum: E-Bike Technical
Topic: controller screw size -- lost my screws
Replies: 4
Views: 400

controller screw size -- lost my screws

So I purchased an ebike second hand at an auction some time back. I took the controller apart to do some recon and I managed to lose the screws that hold the aluminum end caps on. Does some happen to know what size and thread the screws are? This is a typical cheap no-name 12 Fet controller. Thanks,...
by tstephens
Jul 18 2014 2:56pm
Forum: E-Bike Technical
Topic: E bike kit diagnostics
Replies: 46
Views: 2967

Re: E bike kit diagnostics

I should have stated this earlier. The readings should be taken when the battery is not connected to the charger. Was the charger on when the readings were taken?
by tstephens
Jul 18 2014 1:33pm
Forum: E-Bike Technical
Topic: E bike kit diagnostics
Replies: 46
Views: 2967

Re: E bike kit diagnostics

That reading does not make sense. I believe you are taking readings between the wrong pins. All of your readings for individual cells should be between 0 and 3.8v Does your BMS connection look like this? bms.PNG this picture was taken from the manual on: http://www.batteryspace.com/prod-specs/6128_2...
by tstephens
Jul 16 2014 12:20pm
Forum: E-Bike Technical
Topic: E bike kit diagnostics
Replies: 46
Views: 2967

Re: E bike kit diagnostics

Take a reading from pin 15 and the red wire, I believe that is the 16th cell.
by tstephens
Jun 27 2014 10:56am
Forum: Battery Technology
Topic: Vpower / CamyCC Battery LifePo4 48v20ah rebuild
Replies: 30
Views: 2886

Re: Vpower / CamyCC Battery LifePo4 48v20ah rebuild

I wanted to post an updated to close out this thread. I ended up giving up on rebuilding the pack. Many of the cells would not hold their voltage and would continue to drop. In additional to the voltage drop I noticed that some of the cells were off gassing a strange odor. I did not want to invest a...
by tstephens
Mar 19 2014 3:54pm
Forum: E-Bike General Discussion
Topic: Recommendations for a BMX hub build?
Replies: 16
Views: 1454

Re: Recommendations for a BMX hub build?

In your spreadsheet you list the wheel diameter as 26", but in the simulator you have it as 20".
by tstephens
Mar 13 2014 2:18pm
Forum: E-Bike Technical
Topic: shopping list for battery build
Replies: 10
Views: 760

Re: shopping list for battery build

e-beach wrote:Just remember you shouldn't go over .5C continuous on these batteries
This is a critical point to consider. The discharge rating will impact your overall usable capacity. .5 * 9Ah = 4.5Ah usable
by tstephens
Feb 21 2014 11:58am
Forum: E-Bike General Discussion
Topic: Triangle battery bag
Replies: 39
Views: 5623

Re: Triangle battery bag

I read back in this thread that he made someone else order by sending a check or money order. All over his site he has logos and stuff saying he accepts paypal. This business practice seem shadier than ordering something off an infomercial and sending a check and waiting 4-6 week. I thought the sam...
by tstephens
Jan 15 2014 3:21pm
Forum: Battery Technology
Topic: Vpower / CamyCC Battery LifePo4 48v20ah rebuild
Replies: 30
Views: 2886

Re: Vpower / CamyCC Battery LifePo4 48v20ah rebuild

My original pack had 18 cells in series. I should be able to reconfigure the good cells into 16s14p configuration. At 1.1Ah per/cell, this will be ~15.4Ah . Actual capacity will be less due to the cells being used. I went ahead and purchased some Belden tinned copper tubular braid/ground strap 5/16"...
by tstephens
Jan 14 2014 6:53pm
Forum: Battery Technology
Topic: Vpower / CamyCC Battery LifePo4 48v20ah rebuild
Replies: 30
Views: 2886

Re: Vpower / CamyCC Battery LifePo4 48v20ah rebuild

I cut out the bad strings. Now I am charging up the good strings. This is taking forever without a single cell lifepo4 charger with hvc due to the manual monitoring and my paranoia of overcharging. I have a charger on order, just waiting for delivery. In parallel I'm modeling different pack layouts ...
by tstephens
Jan 14 2014 6:47pm
Forum: Battery Technology
Topic: Homemade Battery Packs
Replies: 1627
Views: 435543

Re: Homemade Battery Packs

What sizes of copper braid are you using for the connections?
by tstephens
Jan 12 2014 10:36am
Forum: Battery Technology
Topic: Vpower / CamyCC Battery LifePo4 48v20ah rebuild
Replies: 30
Views: 2886

Re: Vpower / CamyCC Battery LifePo4 48v20ah rebuild

The bms is not connected at this point. So the fault is definitely in the battery. Is there a way to test the bms without having all of strings functional/present? If I cut out the bad strings and make this pack 12s I assume I add another new 4s pack in series to have a functional 16s pack. What are...
by tstephens
Jan 12 2014 1:41am
Forum: Battery Technology
Topic: Vpower / CamyCC Battery LifePo4 48v20ah rebuild
Replies: 30
Views: 2886

Re: Vpower / CamyCC Battery LifePo4 48v20ah rebuild

Here is an update on the battery pack. Strings 3, 9 and 15 will not hold a charge. The voltage drops off very quickly after removing the charger. I'm guessing there is an internal short in these strings. The rest of the strings are all at approximately 3.25v and are holding the partial charge just f...
by tstephens
Jan 10 2014 6:21pm
Forum: Battery Technology
Topic: Vpower / CamyCC Battery LifePo4 48v20ah rebuild
Replies: 30
Views: 2886

Re: Vpower / CamyCC Battery LifePo4 48v20ah rebuild

Thanks for the clarification.

I hooked everything up with alligator clips and moved the charging/monitoring setup to string 6. The voltage is now 3.07v @ .88A (1.878v prior to charging).

What should I expect to see with respect to the current measurements as I approach 3.4v?
by tstephens
Jan 10 2014 3:49pm
Forum: Battery Technology
Topic: Vpower / CamyCC Battery LifePo4 48v20ah rebuild
Replies: 30
Views: 2886

Re: Vpower / CamyCC Battery LifePo4 48v20ah rebuild

Amberwolf - Your http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=22750&start=0 thread was my inspiration for even considering tackling this project. Right now I have a cell phone charger (5v 800mA) hooked up to string 2 to see if I can get it to charge up. The charger leads are being held ...
by tstephens
Jan 10 2014 2:12am
Forum: Battery Technology
Topic: Vpower / CamyCC Battery LifePo4 48v20ah rebuild
Replies: 30
Views: 2886

Re: Vpower / CamyCC Battery LifePo4 48v20ah rebuild

I managed to get the battery fully unwrapped tonight. My original voltage readings were verified on the cells themselves, so this does not appear to be a faulty sense wire. Here is picture of the battery unwrapped and filleted open. battery unwrapped 2.jpg battery unwrapped.jpg I started to take vol...
by tstephens
Jan 09 2014 6:16pm
Forum: Battery Technology
Topic: Vpower / CamyCC Battery LifePo4 48v20ah rebuild
Replies: 30
Views: 2886

Re: Vpower / CamyCC Battery LifePo4 48v20ah rebuild

Thanks for the replies. I'm thinking breaking the pack down into a usable Ahr size is the best approach, limiting my investment in time and $$. This battery is of unknown condition, I assume it has been sitting discharged for quite some time. One of the end cells was dented/crushed at the top. I had...
by tstephens
Jan 09 2014 3:56pm
Forum: Battery Technology
Topic: Vpower / CamyCC Battery LifePo4 48v20ah rebuild
Replies: 30
Views: 2886

Vpower / CamyCC Battery LifePo4 48v20ah rebuild

EDIT: I gave up on this repair, but wanted to add additional info on the BMS pin out in case someone else needs it. I picked up my first eBike at a local auction this week. I got it for a steal, but the downside is the battery pack will not charge over 40.8V. The pack is one of those duct tape Vpowe...
by tstephens
Dec 19 2013 6:13pm
Forum: E-Bike Non-hub Motor Drives
Topic: My first ebike
Replies: 3
Views: 575

Re: My first ebike

This thread should be moved to "E-Bike Non-hub Motor Drives". I believe there are other bafang owners that have experienced similar problems. You might want to change the title to "Bafang crank drive throttle problem"
by tstephens
Nov 14 2013 11:18am
Forum: E-Bike General Discussion
Topic: Ch00paKabrA Second Build
Replies: 10
Views: 1784

Re: Ch00paKabrA Second Build

How did you wire the Bosch batteries up? They have that strange connector interface on them.