New controller

Nealh

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Parsons

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Thanks for the reply buddy I have been looking at that one on AliExpress what is the minimum voltage that can take plus have you got a link to say maybe 1500-watt one
 

wheeliepete

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That controller on Aliexpress in Nealh's link will give you over 2000 watts with a fully charged 48v battery. Ignore the wattage rating and look at max. amperage rating. 40 amps x 48v = 1920 watts. You will need a good spec 48v battery to run it.
 

Parsons

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Thanks yes it's all about the batteries iam running 22v 6s lipos at the moment wired parallel and series to give me 52 volt fully charged and 20 amp hours if you think there is a controller that will match the batteries please let me know
 

wheeliepete

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Controllers are either 36 or 48v, so you are stuck in the middle with that setup. One option is to run a 36v controller, BUT only charge your battery cells to 4.1v, giving you 49.2v pack voltage, which is just under the max. for a 36v controller. Anotherkiwi on here has been doing this for a while with success. What is the spec of the motor you are running?
 

anotherkiwi

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Thanks yes it's all about the batteries iam running 22v 6s lipos at the moment wired parallel and series to give me 52 volt fully charged and 20 amp hours if you think there is a controller that will match the batteries please let me know
What charger are you using?

My chargers have always been set to 4.15v per cell which is the recommended level to preserve LiPo and get more charge cycles.

4.15v x 12 = 49.8 but in general after balancing etc the battery is at about 49.2v

I am using a KT 36v 15 Amp controller and see peaks of >715 W or so. This doesn't work well in warm weather, the controller gets too hot but since November I have had no issues. My remaining problem is that I continue to spin too fast a cadence and get back EMF cut outs.

I will get myself a KT 36/48v controller mainly because I am interested by 16 or 17 Amps and will make setting LVC easier. At the moment I am my LVC - I watch the voltage and as soon as I get near 43.8v I charge. During work season I charge every two days which means at about 46-47v.

Hope that helps
 

Parsons

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Might be 50v mate iam using the sky RC Q200 charger my controller is 36/48 v 800w it not compatible with the ktlcd3 display that's why I'm looking for a new one
 

Parsons

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I thought you can't add a 2s lipo mixing it with 6s lipo I've seen this on AliExpress36V/48V 500W-800W 35Amax Brushless DC Motor Controller Ebike Controller +KT-LCD3 Display One Set
 

anotherkiwi

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I thought you can't add a 2s lipo mixing it with 6s lipo I've seen this on AliExpress36V/48V 500W-800W 35Amax Brushless DC Motor Controller Ebike Controller +KT-LCD3 Display One Set
You can series any size LiPo you want but is is highly recommended they are the same Ah, I also run 4S and 6S 10 Ah LiPo for 37 volts.

You can't parallel different sizes. You could series 3 x 2S then parallel with a 6S though.
 

Parsons

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So say for example if I've got 2 10000ah and 2 5000ah wired in parallel would I get 15000ah as you saying you cannot mix the capacity
 

anotherkiwi

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All 6S?

If you parallel a 10 Ah battery and a 5 Ah battery you will get 5 Ah. You will get the capacity printed on the label however and not the usual 80% if you use them alone.

My big battery is 2 x 10 Ah 4S paralleled and 2 x 10 Ah 6S paralleled then connected in series for a 16 Ah 36v battery.
 

Nealh

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Don't dismiss the matching of controller amp rating and battery discharge rating, typically with lipo what ever the C rating divide it by 4 to be more realistic esp with Multistars.
 

Nealh

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Multistars are 10c rating #but in reality stick to 2.5c x ah for max amp discharge.
In parallel ah is accumulative as it C rate but in series only voltage is accumulative.
 

Parsons

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Thanks my mate building a ebike kit but got 4 multistar batteries like me 6s could only get 2 10.000 and 2 6.000 ah batteries that's all they had in stock wiring the same as me parallel and series
Would he get 16000 ah or 6000ah
As mentioned you not supposed to mix different capacities
 

Nealh

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With all being 6s you can connect three ways to get 16ah as below as all are 6s it makes like simpler.

A.
2 x 10ah in series = 12s/44.4v x 10ah.
2 x 6ah in series = 12s/44.4v x 6ah.
If you then parallel them you still get 12s/44.4v but the ah is accumulative to so is 16ah, you end up with 12s/44.4v x 16ah battery pack.

B.
1 x 10ah & 1 x 6ah in P = 6s/ 22.2v x 16ah.
1 x 10ah & 1 x 6ah in P = 6s/22.2v x 16ah.
Connect in series for 12s/44.v x 16ah.

C.
Alternately run each pair as a single pair.
What ever you do use lipo alarms /voltage gauge and don't go below 3.6 - 3.5v per cell.

B is usually the preferred method.

If you connect 1 x 10ah & 1 x 6ah in series you will only have 12s/44.4v x 6ah battery, as once the 6ah of the lower pack is used up the pack is effectively spent despite one pack still being at 40%.
 

Parsons

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I understand now mate he's connected them in the explanation B that you have written down