Brushless questions

[dschigoda]

I have experience with setting up nitro hydros, but not electric.

I am building a 1/16 scale hydro (22.5" x 10"). The kit seller recommends a Leopard 4420 kV 4 pole motor (2S), or a 2250 kV 4 pole (3S).

Are all brushless 4420 kV 4 pole motors pretty much equivalent, regardless of brand?

 

[Steven Bryant]

To put it simply No, the best 4 pole in runner motor is the NEU motor followed by TP then Leopard. My preference is NEU

 

[RaceMechaniX]

No they are not Dave, but there are some decent quality reasonably priced motors out there. You could also look at HET and TP motors as budget minded alternatives to the Neu's.

For a 1/16 scale, you might consider a motor like the Castle 1415 1Y car motor and use a cooling jacket. 2400kv on 4S with a small 40mm prop will be plenty fast.

Tyler

 

[Mark Bullard]

Why would all 4420 KV 4 pole motors not be the same?

 

[RaceMechaniX]

Quality is the big one. Also the kv does not directly indicate the size. You can have two ~4400kV motors, for example a Neu 1515 0.5Y versus a Neu 1112/1.5D. The 1515 has twice the torque. Both are 4-pole.

TG

 

[Mark Bullard]

True but the two motors in your example are nowhere near the same motor. The later is going to pull higher current than the other one. It is the difference between a Y connection and delta connection.

 

[RaceMechaniX]

Exactly my point, but they are both 4 pole motors with similar kv. Most guys are familiar with can sizes and what should be used, but if the OP was unsure I wanted to make the point there are differences. The recommended Leopard looks like a 2845 based on the kv match although that is a tiny motor.

TG

 

[raptor347]

The OP is talking about a tiny boat. A 28 series leopard or 11 series Neu would be appropriate.

 

[dschigoda]

Yes, it is a Leopard 2845 motor. From the link below, you can see that they sell several versions (different kV) of this 2845 size motor.

http://www.offshoreelectrics.com/proddetail.php?prod=leo-2845&cat=148

They recommend 4420kv for 2s lipo, 2250kv for 3s lipo. , but there must be a typo on their web page, because they don't seen to offer a 2250kv.

Just

2230KV LBP2845/4Y 30A 800W 2550KV LBP2845/3.5Y 32A 800W

And yes, this is a very small hydroplane, 22.5" x 10".

Just from these few posts, I am learning quite a bit. A guy on another form suggested that a Leopard 2845-3650 might be better, but he's not tried it.

My going from nitro to electric - the number of choices available gets me a bit confused at this point.

1. 
   

 

[Mark Bullard]

Ok what is the numbers that I see on these motors behind the KV? See 0.5Y, 1.5D, and 3.5Y. I do know what the Y and the D stand for but what are the other numbers?

 

[RaceMechaniX]

Mark,

Usually it is a reference to the number of turns, however it is not a direct reference for all motors. i.e. a 1Y is not really a 1 turn wye wind motor for some vendors like Neu. I believe Leopard and others actually identify with the correct number of turns in the stator. Compared to Neu which starts at an arbitrary minimum. A Neu 0.5Y maybe actually be a one turn Wye. A Neu 1.5Y is likely a 3 turn Wye and so on.

TG