Charging my 48v ebike ?

[snowcrow]

  Just got my 48v ebike kit installed and looking to charge the 48v 12ah SLA battery pack on my 12v system without breaking anything.   The AC to DC charger is only 90 watts max. (60vdc @ 1.5amp) The big question is, will my modified sign wave inverter toast the charge, or my I good to go?  Just like to know if anyone else has done this, and killed their charger! This charger was not cheap!  Blessings, Snow Crow

[TomW]

Crow;

No idea on whether it is "safe" or not, but in the interest of accuracy and good search results later you might want to reset "sign wave" in your vocabulary to "sine wave".

Tom

[snowcrow]

Oops!!

[Bruce S]

snowcrow;

 The 48V charger will be just fine

I use a small 150watter to run the e-bike charger on our daughter's bike, it has 18Ahr's worth on NiCds on it and has been doing just fine. The SLAs it came with were POSes :-)

The unit we use; I picked up at a Pilot truck stop while on sale for less than $20USD and plugs into a cig outlet, that is merely connected to my bank on my HF panels.

Been doing it this way for months now.

Which e-bike did you purchase?

We picked the E-xtreme 550watter.

Cheers

Bruce S

[snowcrow]

  Thanks Bruce, I've got a couple small inverters (400 and 375 watt). I purchased the Crystalyte Roadrunner, it came with a 48v 25amp (1200watt)controller, rear hub motor (already laced on steel rim), and throttle with power, low volt LED's  It go right along on level pavement, 25mph to 35mph, 16 no peddle miles and does short steep hill fine as well.  Blessings, Snow Crow

[Bruce S]

snowcrow;

 Very nice set.

Watch those batteries, at that level you're probably getting below the 50% on power level.

I built a NiCd pack for ours due to the rough use these e-bike can give SLAs.

Since I was too lazy to build a proper charger I just used the current one and by using the C/10 I setup a timer before the charger, made sure the voltage wasn't too far off and that's it.

Plus they weigh less.

Cheers

Bruce S

[snowcrow]

 I'm saving my money up for a 48v 20ah LiFePO4 pack The power output is the same full charge to empty :>  A 14.8 mile ride pulled the SLA's down to 50%, thats with peddling of course!!   Blessings,  Snow Crow

[zap]

I'm glad you're making progress Snow Crow.

I was wondering the same thing.

I picked these two up last night, one of the chargers was old, original, and obviously has a good size transformer in it because it's a brick! (about the same size as a brick also)  I used my old Xantrex Power pack on it and it worked fine.

The other charger is newer, about 1/4 the size and weighs next to nothing, I assume it's all electronic.

I've always seen warnings on inverters warning about plugging in battery operated tool chargers and such so I was reluctant to try the inverter on that one.

Going by Bruce's experience, it seems like it would be OK.

Snow Crow how about some pictures?  Or are you saving those for a diary entry?

On a side note... Bruce, do you still get NiCd packs?

[snowcrow]

Hey zap, nice little beach cruisers you have there ;> Looks like they fold up, great for taking on vacation!!  Yes, I'll be doing a diary entry soon and post some pictures. Safe travels, Snow Crow

[ghurd]

The heavy transformer types run a little warmer.  And I think they charge the battery a little higher V if they are 'dumb chargers'.

I called a couple tech depts about running switcher battery chargers on MSW, and was told it was fine.  So far, so good.

I do recall someone had trouble with a smart charger on MSW, but it didn't blow up.

G-

[snowcrow]

  Thanks ghurd, it always helps to have a second opinion  It is a switching battery chargers by the way.   When I get the Li pack I'll be getting a new and more expensive charger for it :| so now is the time to work out any issues!    Blessings, Snow Crow

[Bruce S]

zap;

 Yes I do

 As in the past, I'm very careful of who I send these to, they will need rewiring to handle higher current ratings and can quickly become dangerous if handled wrong.

Both you and SC have postings that easily prove you can work with these.

They are individual packs that must be re-soldered for your particular voltage and Amp rating.

Those bike are nice! 36V? internal motors?

Let me know your ratings and possible distance needs and I'll see what I can do.

Snowcrow, same for you. If you're up to doing some rebuild and rewiring I can send them along too.

Need shipping paid for but that's about it.

each small pack is wired for 18V and rate 1.3Ahr, but are very customizable and durable, the wires on them are only 22 - 18ga.

On those LiFePo sets, you might drop Amanda an email asking about her experiences, she's got a much larger set either on order or in hand and will have tons more knowledge.

They aren't as forgiving as NiCds, I don't think, but have no working knowledge of them.

Bruce S

[zap]

Bruce,

I'm not sure what posts you refer to, I would think most of my posts would tell people I can only be trusted with round tipped scissors... dull ones at that!  : )

Actually I have disassembled and repaired a few tool packs in my day and no serious smoke has been seen to date.

I got the bikes of Craigslist, I couldn't pass on the price.  They are the Currie E-Folder model.  The original owner got them in 2001 and I got them from his sister.  She had them tuned up and had new batteries installed last year or the year before with the intent of riding them but never did.  They can't have more than 100 miles on them and I wouldn't be surprised if they had less than half of that.

24v external motor, 7 speed, folding.  Here's a closeup of the motor.

 



Here's a place with a kit that's no longer available, my drive unit is somewhat similar.  Click on the picture of the kit for a closer look.

I weighed the bike today, 60 lbs!!!  About 17 lbs of that is the battery and it's bag, internal tray, and wiring.

I also did a test ride and rode it till I saw a fairly steady 22v under load from a meter I mounted on the handlebar.  30 minutes, 5.9 miles, 11.6 mph average, all with out any pedaling.  I also put the Kill-A-Watt on the charger afterwards and about 4 hours later it was showing 0.13 Kwh.  I didn't think that was too shabby a ride on about $0.013 worth of Xcel Energy.

I bought the bikes with the intention of turning at least one into a pusher trailer but the bikes are in such good shape that I'm having second thoughts on it now... plus they are fun!  I was also thinking about tweaking the voltage higher and see what happens.

So.... Bruce I appreciate the offer and will keep it in mind... thanks.  I'll let you know what I come up with.

Snow Crow, I apologize for hijacking your post, it wasn't intended.

 

[snowcrow]

   Bruce, what is the continues discharge rating ("C" rating) on the cells?   Are they used?   I need at least 35 amps continues discharge for the controller to work properly.  At 18v 1.3ah I would need a truck load (3s x 10p = 30 Packs) to keep up with power demand when climbing hills,(up to 1.2kW) and still have any range!!   Thanks for the offer Bruce, I'll keep it in mind.  No matter which I go with NiCad or Li, I'll have to change the firing cap, they're only rated for 63v, need 100v to be safe :|!!   I'll be wiring in a "Watts-Up" meter this next week just to see what the real power usage is for sure, on this hilly terrain, and plan any upgrade accordingly.    Blessings, Snow Crow

[snowcrow]

  No problem zap, might as well keep all the ebike talk here :>  Not too bad a range and speed for a beach cruiser. At 60lbs., it must be an all steel frame?! My mountain bike is weighs 80lbs., SLA's and all :> (aluminum frame)   Blessings, Snow Crow

[TomW]

Snowcrow;

If they are the same packs I got and they are I am fairly certain. each 18V pack is approx. same volume as a foot long 2X4 stick of lumber. Light, too.

Not near mine to get an actual measurement but thats from memory. I think 30 would fit in a couple shoe boxes.

Maybe bruce will give up the dimensions.

Tom

[Bruce S]

All;

  My bad, should've put the numbers for the packs up earlier.

I'll put them here, then with a couple pics and full numbers in a photo upload.

Tom is correct they are the same packs.

They are used, but fully tested and comes with an energy rating on a tested sticker print out. This is mandated by our company.

I usually try to send them out as paired as possible. i.e. 90% with like or 111% with like. The packs are nominally rated at 18Vdc 1300mAh. and they are sub-c in size; packed in a 5x3 configuration.

ea pk weighs 27oz (765 gm) with dems of L=8.5in(260cm) W= 2.750in(84cm) H=1in(31cm)

As for energy available I have drawn 10A continous , measured using a watts-up meter as well.

My main reasoning for going with these, is beside the fact I get them pretty much free, is the ability to draw these down twice as much as an SLA, still have power left and the batteries will come right back up.

On our daughter's e-bike 4 12Vx18Ahr batts weigh in at 80lbs total and I had her make sure to not draw them down past the 30% mark or middle (yellow) part of her meter.

With the pack I built up, using these, I split them into 12V set due to hers being 48V, this gave me 12V packs at 18 oz ( 511 gm) yet still at 1300mA. I then wired them into packs of 12 for ~16Ahr and then into 48V, that's only 48 packs and they fit very well into the area for the SLAs.

weight comes in (including tin that replaced 18ga wire) 50lbs. and back saving:)

The e-bike now can go right up to 45kph and the people at the Missouri Botanical gardens ( where she does volntr work) thinks it's great.

Cost to charge last time I borrowed a kill-o-watt if plugged into mains was 25 pennies for a full week of daily riding /charging. Saving for not having her on CAR insurance is full tilt $$$ :-)

Hope this helps.

SnowCrow: Understood on the holding off, to get these into a working set, needs to be well thought out and planned.

Zap, that currie is a heck of a find!! at 24Vdc the saddle pack on the back could hold several easily and be lighter too.

For a great wrtie up on how to best re-do these packs, have a look at Norm's posts he's the guru on redoing these packs.

Sorry for the long post.

BUT,Hope this helps

Bruce S

 

[zap]

Thanks for the good description Bruce.

I searched for your daughters bike, is it an XB-508 SPORT?  If so is it hard to pedal that thing?  It looks like the old mopeds where the pedals were only good for getting the thing 'push started'.

To save you some trouble, do you know anyone in the Denver area doing the same thing you do with medical equipment?

I've seen some of Norm's post where he stacked them up in tubes.  Did I miss some others?  I guess I'll have a look back at his posts... I love his posts, he's always doing something outside the box!

[dnix71]

I have the 24v Currie mountain bike from Walmart. The sla's that came with it don't put out enough current at full throttle, even fully charged and new. The bike is also obscenely heavy (about 100 pounds) with an extra battery pack.

I used a microphone case and two used sla's from an APC UPS that failed to make the second pack. I haven't messed with the voltage for fear of damaging the controller.

If I go hard on the throttle, the handlebar lights go green to yellow to red almost instantly, but recover fully when I back off. Going easy on the throttle works fine. I've gone 12 miles on batteries alone to work, then charged them back up in three hours.

Lithium Iron Phosphate costs too much for me now, but that seems to be the future for ebikes.

[snowcrow]

  Hi dnix71, in my opinion a 24v system is just not powerful enough for the average adult.   I weigh 170 lbs. and my bike is 80 lbs. that 250 lbs. total.  The 48v 25amp system I bought is just about right :> !! At full throttle it produces 1200 watts = 1.6 hp or 885 ft-lbs/s,  making for a enjoyable ride.  The 24v system would need to draw 50 amps at full throttle to get the same performance. So... a <100 lbs. rider is it for the 24v system, and about a <175 lbs. rider for a 36v system.     Blessings, Snow Crow

[dnix71]

The federal limit for an ebike to be protected as a "bicycle" is 750 watts. Florida, on the other hand says 20mph on level ground, but doesn't mention motor power.

http://veloteq.com/laws_florida_electric_bicycles.htm

My Currie only goes about 14mph and uses 450 watts, so it's a bicycle by both definitions and under Florida law I can ride it on the sidewalk, which is where I prefer. The streets are simply too narrow and the cars careless and fast.

[snowcrow]

  Yes, The federal limit for an ebike to be protected as a "bicycle" is 750 watts, but that is in reference to the bike being ridden by a person weighing 170 lbs. who's top speed is no more than 20 mph.   That kind of makes the law unenforcible don't you think!?  If you were to stay within the limits of the law as far as speed goes, I think you'd be fine, at least that is what local law enforcement has told me.  Blessings, Snow Crow

[spinningmagnets]

There are many existing systems that are sold in the US with a "label" stating 750 Watts, but thats at a stated 36 volts. The construction clearly shows they are capable of using 48-72 Volts which would equal 30%-100% more power.

If you're not driving in an unsafe way to draw attention, you should never be stopped and questioned by any authorities. Even if stopped, most police would not know about Ohms law or how to measure it (if a volt meter was even available)

A 1,000 Watt motor could even have a 750W label.

To me the big benefit of the E-bike is when you reach an uphill, no sweat, and no slow-down. Plus accelerating away from a daydreaming car driver (oopsies! did I break your bike and crush your leg? I am SOOOOO sorry).

I'm working towards a stealth set-up with a rear hub-motor and saddle-bags to hide it.

[snowcrow]

  Hi spinningmagnets, That setup does work great :>!!   I've been riding for a month with the that same setup and as long as you're peddling, no one gives you a second glance.   I like to accelerate up inclines "no peddle", once in a while, just to see the puzzled look on peoples faces Blessings, Snow Crow

[Bruce S]

Zap;

   It's not so hard, except trying to go up hill of course. The pedals are kept under the seat just in case the batteries get too low or there a problem. They're easy to connect and pedal. Correct it's the XB-508.

The controller keeps her from going over 44kph ~25mph.

Not too hard to "fix" but not necessary on St.Louis' city streets. All the big bikes like it and are pretty cool about it when at Ted Drew's ( Ice cream shop).

We have lots of equipment up in the Denver area, even have a programmer up around there, BUT no way to have them safely pull the batts from the equipment.

Norm is great when it comes to re-working these into new uses.

Bruce S