Extending ESC wiring?

[CornelP]

Hi guys, I have a small issue with an ESC: it is quite bulky and the wires very short.
The ESC is about 150mm (6") long with wires no longer than 50mm (2"). I can only install it lengthwise in the boat, so i have to extend either the battery wires or the motor wires by about 150mm (6").

The question is: which is the less dangerous option? Extending motor wires or battery wires?

Also have to add that all external wiring on the ESC is doubled, 12AWG each. I can extend the leads with either 12AWG or 10AWG, and It is almost impossible to actually replace the wires (preferred option).

Cornel

[Fluid]

This topic has been extensively debated on helicopter sites. Castle's owner weighed in, saying that extending the battery wires is the "best" way to go. He recommended adding caps when you do this.

The problem with longer motor wires is interference/delay of feedback from the motor to the ESC. Long wires make it easier for the controller to "lose" the ESC rotor position.


.

[CornelP]

THANK YOU!! I'll give it a try with the extra caps, hope it will be ok.

[ManuelW]

Hi Cornel,

how long are your cables at the moment?
-complete length between battery and ESC
-complete lenght between ESC and motor
(cables lengths of battery and motor included)

I'd always try to keep the wires between ESC and battery as short as possible, if you have to lengthen it adding additional caps is a good thing. Between ESC and motor the length is not that critical and you don't need aditional caps. May only decrease the range of a 40Mhz System.

Best regards,
Manuel

[CornelP]

Hi Manuel, the original wiring was:
ESC-Battery: 50mm (2x12AWG)
Battery-motor: 50mm (2x12AWG)

Required length:
ESC-Battery: 200mm (also 2x12AWG)
Battery-motor: 50mm

Quite difficult adding the caps in the position it's installed (I'll take a picture later today), and the original caps are a bit small: 8pcs Rubycon 220mF 65V. I have another 2 available 1000mF/65V, but it will need a bit of planning...

[don ferrette]

Like Jay said, lengthen the ESC to battery leads and I would up the wire guage to 10AWG, keep the wires between the ESC and motor as short as possible. If space is an issue for adding caps you could always pigtail the cap bank so you can get them in there (I did that on a record trials boat and used 10AWG wires about 4" long) Personally I feel it better to have the added caps there with a little extra wiring to connect them then not have the added protection.

[ManuelW]

Hi Cornel,

as you may read in my post I asked for the complete lengths because I assume your batterys have some cable length as well and what always counts is the total length of cable between ESC and battery or ESC and motor (some CC motors feature quite long cables as far as I have seen for example)

But a total length of 200mm between ESC and battery shouldn't be critial at all and with double 12AWG the cable is thick enough. Double 10AWG wire would be only necessary in real SAW applications as far as my experience says.

If possible I'd make the the cables between ESC and motor longer, to keep the cables between battery and ESC shorter.

BTW: Which ESC featuers 8x 220µF caps, will await the picture of the layout!

Best regards,
Manuel

[CornelP]

Ok, this is the boat and the ESC... as you see my dilemma is quite BIG...
Because of the position of the motor, I should either extend the motor wires by under 4" or the battery wires by about 6" (mainly because I will use some batteries that have no cable, just bullets soldered to tabs).
I did manage to change the wires going to the motor as I did not like the soldering too much on them, so I'll see what decision I'll take...

[ManuelW]

Hi Cornel,

I'd say no drama at all. Use the ESC like in the last picture and either extend the wires from the ESC to the motor or if you use high quality bullets make some adapters with male bullets at one side and female ones on the other side. Extending the motor wires for about 4" is not even important to mention I think.
And just keep the battery wire as short as possible.

That's the way I'd do it.

Best regards,
Manuel

[don ferrette]

Hi Cornel,

I'd say no drama at all. Use the ESC like in the last picture and either extend the wires from the ESC to the motor or if you use high quality bullets make some adapters with male bullets at one side and female ones on the other side. Extending the motor wires for about 4" is not even important to mention I think.
And just keep the battery wire as short as possible.

That's the way I'd do it.

Best regards,
Manuel

Not looking to start any trouble by any means but I'd like to here why you feel it's better to extend the motor leads instead of the battery leads?

[ManuelW]

Hy Don,

well first thing is you have to think about why you need caps. The thing is that through the engine you get ripple currents. And the important factor is the inner resistance of the batterys. So the worse the batterys the more work for the caps. But it does not only depend on the batterys, also bad connectors or long wiring increases the inner resistance. Thats why most ESC manufactures recommend to add caps, especially with long wires.

Therefore I think its always good to keep the wires as short as possible/use high quality bullets and for some ESC's to add some caps even with stock cable lengths. It just doesn't hurt that much to have additonal caps except when you have to connect the batterys.

Now about the wires between ESC and motor: As Jay already "told" me in another thread a very well known ESC manufacturer like Schulze writes in the description that you should keep the wires between ESC and motor less than 10cm or about 4". But I already had contact with several other ESC manufactures and they all told me that wire length between ESC and motor is uncritical but it is not a bad idea to pleach them (hopefully correct translation) if they are quite longer than normal. And as I really wanted to know I contacted Schulze themselves. And they wrote me that the biggest problem with long motor wires are interferences with the 40Mhz System which can reduce the range. From their ESC's point of view (Schulze 40.160WK) they wrote my that a wire length up to 100cm or 25" between ESC and motor should be uncritical. That also explains why in Helis the keep these wires short. Most of them don't need that massive power like in the boats we run and having a good transmission to the Heli is an absolute must and more important than having cool caps. But with 2.4GHz it shouldn't be a matter anyway.

Well I'd never recommend to have that long wires anyway and I'm always a fan to keep the wires as short as possible. But from my side if the question arises like in Cornels boat I'd lengthen the motor wires in favour of shorter wires between ESC and battery.

Wish a nice evening,
Manuel

[Brushless55]

Hy Don,

well first thing is you have to think about why you need caps. The thing is that through the engine you get ripple currents. And the important factor is the inner resistance of the batterys. So the worse the batterys the more work for the caps. But it does not only depend on the batterys, also bad connectors or long wiring increases the inner resistance. Thats why most ESC manufactures recommend to add caps, especially with long wires.

Therefore I think its always good to keep the wires as short as possible/use high quality bullets and for some ESC's to add some caps even with stock cable lengths. It just doesn't hurt that much to have additonal caps except when you have to connect the batterys.

Now about the wires between ESC and motor: As Jay already "told" me in another thread a very well known ESC manufacturer like Schulze writes in the description that you should keep the wires between ESC and motor less than 10cm or about 4". But I already had contact with several other ESC manufactures and they all told me that wire length between ESC and motor is uncritical but it is not a bad idea to pleach them (hopefully correct translation) if they are quite longer than normal. And as I really wanted to know I contacted Schulze themselves. And they wrote me that the biggest problem with long motor wires are interferences with the 40Mhz System which can reduce the range. From their ESC's point of view (Schulze 40.160WK) they wrote my that a wire length up to 100cm or 25" between ESC and motor should be uncritical. That also explains why in Helis the keep these wires short. Most of them don't need that massive power like in the boats we run and having a good transmission to the Heli is an absolute must and more important than having cool caps. But with 2.4GHz it shouldn't be a matter anyway.

Well I'd never recommend to have that long wires anyway and I'm always a fan to keep the wires as short as possible. But from my side if the question arises like in Cornels boat I'd lengthen the motor wires in favour of shorter wires between ESC and battery.

Wish a nice evening,
Manuel

wow, that's interesting
because I've heard the oposite