Search found 16565 matches

by dnmun
Sep 13, 2015 10:28 pm
Forum: Battery Technology
Topic: Recommendation for 72V 25ah pack (commuter)
Replies: 7
Views: 469

Re: Recommendation for 72V 25ah pack (commuter)

it would be best if one of those guys who threw their battery away would have saved them for you. i bet your current pouches have more than 20Ah too. but i see you said that you did not get the pack from sun thing guy. i doubt if you could do a precise capacity measurement. maybe the pack you bot wa...
by dnmun
Sep 13, 2015 9:29 pm
Forum: Battery Technology
Topic: Recommendation for 72V 25ah pack (commuter)
Replies: 7
Views: 469

Re: Recommendation for 72V 25ah pack (commuter)

why not buy another 8S from the sunthing guy and make it to 24S with a 24S D131 BMS?
by dnmun
Sep 13, 2015 8:41 pm
Forum: Battery Technology
Topic: Data logging balance charger
Replies: 15
Views: 1426

Re: Data logging balance charger

yes, the D141 from bestechpower will record data too up to 13S, lots of data including internal resistance.
by dnmun
Sep 13, 2015 7:01 pm
Forum: E-Bike General Discussion
Topic: Problem hub motor/battery cuts out under heavy load
Replies: 56
Views: 1564

Re: Problem hub motor/battery cuts out under heavy load

can you remove that ground plane from underneath? we need to find the spots on the relay to jumper. the only way to do it is underneath i suspect. you can look and see if you can find how to put a jumper around the relay from the top. if we can make this charger stay on it should work yet.
by dnmun
Sep 13, 2015 5:53 pm
Forum: E-Bike Technical
Topic: Replacement controller nightmare
Replies: 15
Views: 736

Re: Replacement controller nightmare

the hall sensor wires short to the phase wire inside the axle. did you replace the output mosfets on this replacement controller?

i suspect there is a short where the new mosfets were soldered into the new controller.
by dnmun
Sep 13, 2015 5:45 pm
Forum: Battery Technology
Topic: Battery Troubles
Replies: 21
Views: 916

Re: Battery Troubles

they know less than we do. put your battery on the charger and measure the cell voltages with your DVM using the 20V DC scale to .01V. post up all the measurements here.
by dnmun
Sep 13, 2015 2:31 pm
Forum: E-Bike General Discussion
Topic: [SOLVED] Current drop ?
Replies: 36
Views: 1314

Re: Current drop ?

i was under the impression the battery is made up of used laptop cells. is this not the case? there was no BMS and no knowledge of how many times the cells had been over discharged and converted into resistors. i doubt if it is a problem with the kit if the kit is new.
by dnmun
Sep 13, 2015 1:17 pm
Forum: E-Bike General Discussion
Topic: Plugged in battery to power supply and fan broke?
Replies: 23
Views: 989

Re: Plugged in battery to power supply and fan broke?

these people never come back. why they even ask for help and never reply is beyond me.
by dnmun
Sep 13, 2015 5:31 am
Forum: Battery Technology
Topic: Bestechpower BMS
Replies: 216
Views: 24457

Re: Bestechpower BMS

you can use two in parallel with each other if you want to also. if you use one and wanna solder up the shunt then first be certain you have an idea of what your max current is and if it causes the BMS to cut off then solder the shunt a little bit and see if that allows it to work. don't use so much...
by dnmun
Sep 12, 2015 5:53 pm
Forum: Battery Technology
Topic: 24s lipo charger (100.8V) recommendations.
Replies: 4
Views: 513

Re: 24s lipo charger (100.8V) recommendations.

i agree with that. that is a well built charger. more reliable than most. i now recommend bypassing the switch to turn the charger on and off. i think the impedance of the wires from the base resistor to the switch and back to the base of the transistor shifts the transistors a little out of phase i...
by dnmun
Sep 12, 2015 12:39 pm
Forum: E-Bike Reviews & Testing
Topic: ~$1,000 China Electric "Grom" motorcycle review, 68kph
Replies: 27
Views: 5515

Re: ~$1,000 China Electric "Grom" motorcycle review, 68kph

don't confuse him. he already knows more than anyone else. he is the only one riding these scooters so he knows them better than us.
by dnmun
Sep 12, 2015 12:26 pm
Forum: Battery Technology
Topic: 24s lipo charger (100.8V) recommendations.
Replies: 4
Views: 513

Re: 24s lipo charger (100.8V) recommendations.

you should be able to combine a 48V meanwell and a 36V lifepo4 charger together in series to make 101V.
by dnmun
Sep 12, 2015 10:42 am
Forum: E-Bike General Discussion
Topic: Plugging in Mean Well power supplies and it trips the house!
Replies: 7
Views: 226

Re: Plugging in Mean Well power supplies and it trips the ho

was this circuit breaker a GFCI type breaker? you may have a high voltage short to the case that blew the breaker. otherwise removing the ground would have no effect.
by dnmun
Sep 12, 2015 10:40 am
Forum: E-Bike Technical
Topic: Replacement controller nightmare
Replies: 15
Views: 736

Re: Replacement controller nightmare

what was wrong with the old controller? post up a picture of the damage you did to the phase wires when you wrecked. i suspect the phase wires are still shorted to the hall sensor wires from the accident but need to know why you replaced the original controller. is it still around or did you throw i...
by dnmun
Sep 12, 2015 10:31 am
Forum: E-Bike Technical
Topic: Chip Blowing in Controller when under load.
Replies: 10
Views: 514

Re: Chip Blowing in Controller when under load.

Have a commercial built Wisper 905e Electric Bike. A month ago it started to blow the 20amp in the battery pack as soon as you turned it on. Local electronics store has now eliminated the blowing of fuses. The problem now, is that you switch the bike on, all is fine until you start to rev. No matte...
by dnmun
Sep 12, 2015 10:25 am
Forum: E-Bike General Discussion
Topic: Problem hub motor/battery cuts out under heavy load
Replies: 56
Views: 1564

Re: Problem hub motor/battery cuts out under heavy load

no, don't do that. you can solder a wire across the relay and use this charger to see if you can balance the pack. can you take the circuit board out and take a picture of the underside where the relay is located? see if you can follow the trace from the schottky diodes over to the relay. that is th...
by dnmun
Sep 12, 2015 10:20 am
Forum: E-Bike General Discussion
Topic: Do I need a puller for replacing hall sensors?
Replies: 35
Views: 1173

Re: Do I need a puller for replacing hall sensors?

you can take the sun-thing pack apart and split it 3/4&1/4 and put the 1/4 lower in the triangle so it may fit then. the trick is to use a large wire to connect the two sections and then place the sense wire for that node in the middle of the wire you use to connect them. it is easy plus then you ca...
by dnmun
Sep 11, 2015 11:42 pm
Forum: Battery Technology
Topic: [Question] How to test 18650 capcity
Replies: 5
Views: 367

Re: [Question] How to test 18650 capcity

first connect them all in parallel and charge them up to full charge at 4.20V with a big single cell charger. then connect them in series with a watt meter to record the amp hours Ah as you discharge the cells down to 2.70V each. when one cell reaches the 2.7V level then stop and record the Ah on th...
by dnmun
Sep 11, 2015 8:48 pm
Forum: E-Bike General Discussion
Topic: Problem hub motor/battery cuts out under heavy load
Replies: 56
Views: 1564

Re: Problem hub motor/battery cuts out under heavy load

that integrated circuit in the lower right corner controls the relay. it is turning the relay off when the voltage or current reaches a set point and i suspect the two trim pots are for setting the voltage and current. maybe only current where the integrated circuit decides it is essentially fully c...
by dnmun
Sep 11, 2015 8:36 pm
Forum: E-Bike General Discussion
Topic: A2b battery dead how to reverse charge?
Replies: 39
Views: 1397

Re: A2b battery dead how to reverse charge?

yep the first cell is between that top line and the B- the measure each of the next 9 by measuring the voltage from one hole there to the next. where do those paired lines go. the blue blbue, red black and yellow and orange brown. i assume the red and black with the spade clips in back go to the cha...
by dnmun
Sep 11, 2015 8:24 pm
Forum: Battery Technology
Topic: 8S2P 24v Battery – Help needed.
Replies: 31
Views: 1450

Re: 8S2P 24v Battery – Help needed.

we can educate you to the point where you should be able to diagnose it and fix it on the boat if it fails in use. BMS is very simple. the only batteries i have destroyed was because of discharging it without a BMS.
by dnmun
Sep 11, 2015 6:23 pm
Forum: E-Bike General Discussion
Topic: Problem hub motor/battery cuts out under heavy load
Replies: 56
Views: 1564

Re: Problem hub motor/battery cuts out under heavy load

i don't understand why people do not post their pictures in their thread. i have asked the other guy to post his pictures in his thread and he refuses to do it too. can you read the part number on that transistor in the lower right corner and what are those blue things with the white goop connected ...
by dnmun
Sep 11, 2015 5:37 pm
Forum: E-Bike General Discussion
Topic: A2b battery dead how to reverse charge?
Replies: 39
Views: 1397

Re: A2b battery dead how to reverse charge?

post up your pictures in your thread.
by dnmun
Sep 11, 2015 5:36 pm
Forum: E-Scooter and Motorcycle General Discussion
Topic: Need Help on Lithium Upgrade! I'm going the same speed!
Replies: 8
Views: 627

Re: Need Help on Lithium Upgrade! I'm going the same speed!

how did the dealer modify the ebike to go faster than the legal limit? show a picture of the controller and what he did.