Search found 11447 matches

by fechter
Dec 14, 2017 7:54 pm
Forum: Battery Technology
Topic: BMS problem
Replies: 26
Views: 209

Re: BMS problem

All right thank you for this piece of advice but could you be more specific when you re saying a cell is going too low/ the current is going too high? If any cell drops below cutoff (this depends on BMS model. Usually around 2.6v) while it is under load, this will cause the BMS to trip. The cell vo...
by fechter
Dec 14, 2017 12:40 am
Forum: Battery Technology
Topic: Surface resistivity & volume resistivity?
Replies: 10
Views: 108

Re: Surface resistivity & volume resistivity?

It might be worth testing. I've seen that stuff used in medical equipment (for RFI shielding).

Being a foam, the more you compress it, the lower the resistance will be. it can be used as a force sensing resistor.
by fechter
Dec 13, 2017 3:23 pm
Forum: Motor Technology
Topic: extra unused controller wires
Replies: 3
Views: 61

Re: extra unused controller wires

Again, make sure they're well covered, I usually use short pieces of small diameter shrink tubing, and pinch the open end shut while it's still hot. Sometimes this hurts a little. I should find another way. But it hurts less each time I do it. I use needlenose pliers to pinch them closed. Works great
by fechter
Dec 13, 2017 2:51 pm
Forum: Battery Technology
Topic: Surface resistivity & volume resistivity?
Replies: 10
Views: 108

Re: Surface resistivity & volume resistivity?

A property of sheet conductors is the resistance is independent of the distance between points. In your example, if the foam is sandwiched between the cell and a bus bar, you will have something close to the volume number.
by fechter
Dec 13, 2017 12:42 am
Forum: Battery Technology
Topic: Super glue nickel strips to 18650?
Replies: 13
Views: 340

Re: Super glue nickel strips to 18650?

Nope, look around. Some recent work by Micah Toll shows how wrong you solder guys are. Google. Googling resulted in a lot of hits. Not sure which one you are referring to. As far as soldering goes, it would likely be the least expensive route. I've built some fairly large packs soldering and had go...
by fechter
Dec 12, 2017 12:01 pm
Forum: Battery Technology
Topic: Do batteries "waste away" if not used?
Replies: 4
Views: 184

Re: Do batteries "waste away" if not used?

Yes. All batteries deteriorate over time.
Storage conditions will greatly affect how long they live. Properly stored Li-ion batteries can have a pretty long lifespan. I have some that are 10yrs old that are still 80% of their original capacity.
by fechter
Dec 12, 2017 11:57 am
Forum: Battery Technology
Topic: Super glue nickel strips to 18650?
Replies: 13
Views: 340

Re: Super glue nickel strips to 18650?

Super glue won't work. They make conductive adhesive that would work at low power levels, but not something you could use on a bike.

No solder, no weld battery connectors:
https://endless-sphere.com/forums/viewt ... it=VRUZEND
by fechter
Dec 12, 2017 11:34 am
Forum: Alternative Energy
Topic: 24V/48V UPS as an inverter for mini power-wall
Replies: 10
Views: 147

Re: 24V/48V UPS as an inverter for mini power-wall

Being able to use my bike battery worked out really well the last time I had a power failure. In the "old days" I had a 12v inverter that ran off a big lead-acid battery. Short run time, very heavy, and the tendency to leak acid made it pretty unattractive. Now I can grab any one of my several 52v b...
by fechter
Dec 12, 2017 11:20 am
Forum: E-Bike General Discussion
Topic: Got my butt kicked today
Replies: 17
Views: 474

Re: Got my butt kicked today

Glad you're OK. That extra helmet sounds like a great idea. I'd like to find one that isn't full of cooling vents for riding in the cold weather.

Back when I lived in Utah, ice was a problem, but where I live now, it's about once every 20 years.
by fechter
Dec 12, 2017 10:45 am
Forum: E-Bike General Discussion
Topic: hand throttle instead of pedal assist
Replies: 32
Views: 743

Re: hand throttle instead of pedal assist

The sensor output voltages look very similar to a typical throttle. It seems like it may be possible to take the wires going to the sensor and run them to a standard throttle instead. This might be easier to figure out the wires. It would be good to cut things in a way that makes putting them back e...
by fechter
Dec 12, 2017 10:42 am
Forum: Battery Technology
Topic: BMS problem
Replies: 26
Views: 209

Re: BMS problem

Ok thank you. :D But you really don t have any explanation to the fact that the tension goes down while using the batteries? It seems the BMS is tripping for one reason or another. That's what causes it to cut the output. With no load, it will show full pack voltage but this is going through a resi...
by fechter
Dec 11, 2017 5:11 pm
Forum: E-Vehicles General Discussion
Topic: Demagnetized magnet for electronic throttle, help!
Replies: 12
Views: 223

Re: Demagnetized magnet for electronic throttle, help!

If you have multiple smaller (but identical) magnets, you can stack them to get the desired length.

Not sure where you are looking for magnets. One place I've used in the past is Emovendo: http://stores.ebay.com/Emovendo

another one is https://supermagnetman.com/
by fechter
Dec 11, 2017 3:09 pm
Forum: E-Bike General Discussion
Topic: Freewheel Maintenance
Replies: 19
Views: 346

Re: Freewheel Maintenance

I have no idea what Double D 40 is, but it sounds like the title of a movie I would watch 15 minutes at a time. :twisted: Just do a Google image search for Double D 40. :wink: I had one fail when the grease got sticky and the pawls didn't engage fully. Almost hurt myself when it slipped under load....
by fechter
Dec 11, 2017 2:55 pm
Forum: Battery Technology
Topic: BMS problem
Replies: 26
Views: 209

Re: BMS problem

Baptiste wrote:
Dec 11, 2017 10:16 am
Should I connect the amplifier on the B+ an B- instead of p+ and p- ?
You could try that just to make sure the cells are good. It should work but won't give you protection. You could also charge that way but would need to babysit the cell voltages to make sure none go over 4.2v.
by fechter
Dec 11, 2017 9:28 am
Forum: E-Bike General Discussion
Topic: Statorade ferofluid
Replies: 1
Views: 104

Re: Statorade ferofluid

I just drilled a hole, but you need to make sure the drill doesn't hit anything inside and you want to avoid getting any drill chips inside (vacuum cleaner while drilling). The ferrofluid will just run down the side of the motor housing and stick to the first magnet it finds. When the motor runs, it...
by fechter
Dec 11, 2017 9:20 am
Forum: Battery Technology
Topic: BMS problem
Replies: 26
Views: 209

Re: BMS problem

If the BMS 'sees' any cell going below the cutoff point, it will disconnect the load. Measure each cell voltage at the BMS connector and make sure they are all within the healthy range. Try measuring them with the load connected also. Even if it was a LiFePO4 BMS, it should allow discharge with 3.6v...
by fechter
Dec 11, 2017 9:12 am
Forum: General Discussion
Topic: Chinese e-bike
Replies: 5
Views: 144

Re: Chinese e-bike

Any of my packs will hold a charge for over a year if left sitting. Something is draining the pack. Some of the new controllers have features like "anti-thief" that could drain things if left connected to the bike. If the pack drains by itself without being connected, something is wrong.
by fechter
Dec 11, 2017 9:09 am
Forum: E-Bike General Discussion
Topic: hand throttle instead of pedal assist
Replies: 32
Views: 743

Re: hand throttle instead of pedal assist

Any chance it got wet? I've had a similar problem after washing the bike. It started working again after it dried out. Otherwise, could still be a contact that's just barely touching. Wiggling the connectors will sometimes make a difference. The hard part it seems is getting access to the wires you ...
by fechter
Dec 10, 2017 6:47 pm
Forum: General Discussion
Topic: Dirt bike fork on an ebike?
Replies: 14
Views: 219

Re: Dirt bike fork on an ebike?

Double crown forks made for bikes will fit the head tube. If you can find a set of triple clamps for a bike fork that has the same diameter as a MC fork, then you could just slide the fork tubes in and go.
by fechter
Dec 10, 2017 6:35 pm
Forum: E-Bike General Discussion
Topic: hand throttle instead of pedal assist
Replies: 32
Views: 743

Re: hand throttle instead of pedal assist

From the manual: A2B Hybrid Error Codes.JPG Somewhere between the motor or sensor and display. It is probably not having a good connection on one of the pins in the connector. Inspect the pins and make sure none are damaged. Look at the sockets and make sure the metal part inside isn't spread apart ...
by fechter
Dec 08, 2017 8:22 pm
Forum: E-Bike General Discussion
Topic: hand throttle instead of pedal assist
Replies: 32
Views: 743

Re: hand throttle instead of pedal assist

That looks like a great meter (nicer than some of mine). The trick is to make contact with the lines running from the motor connector up to the display unit. The pins on the connector are very small and easy to short. If there is another connector further up the line, it might be easier to probe. Wh...
by fechter
Dec 08, 2017 8:13 pm
Forum: Battery Technology
Topic: So confused, please help (24s 99.6V battery charging/safety)
Replies: 20
Views: 346

Re: So confused, please help (24s 99.6V battery charging/safety)

Just remember that if you charge with more than one RC charger at the same time, they each need their own isolated power supply. You can't run more than one off a single supply or you will have a short (smoke, etc.).
by fechter
Dec 08, 2017 12:05 am
Forum: E-Bike General Discussion
Topic: How To, 50A BBSHD Controller Mod
Replies: 130
Views: 8491

Re: How To, 50A BBSHD Controller Mod

Which model of display is that?
by fechter
Dec 07, 2017 3:28 pm
Forum: Motor Technology
Topic: Adding hall sensors to outrunners
Replies: 422
Views: 78204

Re: Is it work if I place hall sensor head (not a side) facing to magnet?

Not likely. The sensor chip inside the hall only detects in one direction. Hall Sensor orientation.JPG If you place them like shown in your picture, There isn't much magnetic flux going in that direction. It might work but I'd think it would be real prone to timing errors at high load. It looks like...
by fechter
Dec 07, 2017 3:05 pm
Forum: General Discussion
Topic: la Nina rears her ugly head
Replies: 576
Views: 18475

Re: la Nina rears her ugly head

Good time to make sure your fire insurance is up to date.
My daughter lives in Van Nuys, directly downwind of the Creek Fire. The smoke is choking.