New supply from china

[banbury frank]

Hi New supplier from china well worth a look BMS seem to be getting Unreliable with long delivery and rip off on delivery charges


EBike Kits-Elifebike Online Store

Frank

 

[Scimitar]

Cheers, Frank. Just had a look, some interesting stuff there, especially their diy Headway kits.

 

[cwah]

Few members from endlesssphere had issue with this supplier.

Beware guys!

At least with BMSbattery you receive what you expect

 

[Scimitar]

Few members from endlesssphere had issue with this supplier.

Beware guys!

At least with BMSbattery you receive what you expect

Oh, well, perhaps it was too good to be true, as usual. Bummer.

 

[banbury frank]

I Have read the comments on Endlessphere and they are not that bad just go on there and type in on the search button elifebikes I have just had 2 delivery s off Chargers and BMS s and the delivery time was and goods spot on You have no problem if you use Paypal as your payment is safe

 

[OxygenJames]

OK that looks interesting thanks Frank.

Somebody help me out here - there are some motors on their site that say the maximum RPM is 250 - and others that say the maximum RPM is 305 - some even say the max RPM is 365.

Fair enough - now you would think that would be because some are rated 250W and others 350W or 500W - or that some are 36V and others 48V. But......... not so it seems! One of the 36V, 250W motors says the RPM is 305 along with a 500W rated one. So how does that work?

And for a bonus point - what speed on a 26inch wheel does 305rpm work out to?

Any responses gladly received!

 

[flecc]

The internal gearing can determine the hub RPM, as can the coil windings. If you refer to my answer to your other thread question you'll see that ratios of Amps and Volts have different outcomes too.

The 305 rpm in a 26" wheel gives 23.6 mph on the flat, if there's enough power to sustain that speed against wind and rolling resistance.
.

 

[OxygenJames]

Great thanks Flecc. It would seem that my Burisch must have a 305 RPM motor - because 23.6 is about exactly the speed it tops out at.

The pieces are beginning to come together!

 

[OxygenJames]

Well maybe not quite that fast - but getting close to that.

 

[OxygenJames]

OK - so at that site I see the following controller:

"Power:500W

36V 500W Max. Cut-off Current: 21A Discharge Cut-off Voltage: 31V
48V 500W Max. Cut-off Current: 21A Discharge Cut-off Voltage: 42V36V/ 48V"

So it seems to me......... that the 36V variety would deliver a max of 36x21=756W - thats right yes? And yet they call this a 500W controller.......... which I am thinking would be too high for the motor I have? Thinking out-loud.

 

[flecc]

I don't know that motor on the Burisch. Many of the SB motors will stand over 20 amps, at one time the Torq and Quando SB motors had 30 amp controllers and would peak at around 1000 watts gross, and the current eZee motor has a 20 Amp controller.

Your similar motor may be able to cope with 21 amps, but I can't say with any certainty.

Those calculated figures are gross "powers" by the way, the 756 being the consumption of current in watts. No motors are anywhere near 100% efficient of course, so with the efficiency loss deducted, the net continuous power capability which is the actual power output in watts, could be around the 500 watts mark.

 

[OxygenJames]

I don't know that motor on the Burisch. Many of the SB motors will stand over 20 amps, at one time the Torq and Quando SB motors had 30 amp controllers and would peak at around 1000 watts gross, and the current eZee motor has a 20 Amp controller.

Your similar motor may be able to cope with 21 amps, but I can't say with any certainty.

Those calculated figures are gross "powers" by the way, the 756 being the consumption of current in watts. No motors are anywhere near 100% efficient of course, so with the efficiency loss deducted, the net continuous power capability which is the actual power output in watts, could be around the 500 watts mark.

Great thanks Flecc that makes sense.

 

[Deleted member 4366]

OK - so at that site I see the following controller:

"Power:500W

36V 500W Max. Cut-off Current: 21A Discharge Cut-off Voltage: 31V
48V 500W Max. Cut-off Current: 21A Discharge Cut-off Voltage: 42V36V/ 48V"

So it seems to me......... that the 36V variety would deliver a max of 36x21=756W - thats right yes? And yet they call this a 500W controller.......... which I am thinking would be too high for the motor I have? Thinking out-loud.

The watts in the controller's description is normally the power it can run through it for a prolonged period without overheating. If they only have one amp rating, it's usually the maximum, but often they say something like " 7 amps, 14 amps max", which are the continuous and maximum currents it can deal with.

Just remember that amps gives torque and volts give speed, and these are values from the battery. What goes into the motor to make motive power depends on the motor depends on the motor, the speed of the motor and the throttle position.

It's important that batteries, controllers are matched with ratings that they can all handle and must be compatible with the speed and power demands of the rider. You can't just fit a bigger controller and expect more power, although, if your sensible in your choice, you can often improve things, and for every upside, there's always a downside as well.

 

[NRG]

OK - so at that site I see the following controller:

"Power:500W

36V 500W Max. Cut-off Current: 21A Discharge Cut-off Voltage: 31V
48V 500W Max. Cut-off Current: 21A Discharge Cut-off Voltage: 42V36V/ 48V"

So it seems to me......... that the 36V variety would deliver a max of 36x21=756W - thats right yes? And yet they call this a 500W controller.......... which I am thinking would be too high for the motor I have? Thinking out-loud.

In addition to what Dave has posted above, keep in mind that maximum power is generated at about half motor speed under load....you wont generate 500w at top speed. At this half speed point the motor efficiency will be between 60 and 70%, so with your example 756w is reduced to approx. 460 to 530w at the motor, the rest is wasted in heat.

Also the real value will be lower than this due to losses in the controller and wiring...