Wiring Help

[b0wman]

HI, this is my first post here and I'm looking for help regarding the wiring of my very first crawler. I've tried searching but couldn't find a diagram that seemed right for my set up. I have the whole kit built just need to wire everything up but don't know where to start.

I have a Hitec 7950 servo
Traxxas 3s LiPo battery
Futaba 3pl radio
Novak Eiger ESC
Novak Rockstar 35t
Novak 3-Amp High Voltage Universal BEC

I would be super grateful for anyhelp

Semper Fi,
Chris

 

[AutoCrawler]

Generally, the ESC and the Servos plug into the receiver (RX). The motors plug into the ESC, the battery plugs in to the ESC - you are done. With the external BEC there are some additional things you have to do.

Here is a typical BEC wiring diagram. Not yours but they moslty wire up the same assuming you are using a 5v or 6v output BEC.
CC BEC Wiring Diagram

The important thing is that you need to disconnect the +ve RED wire from the lead that goes from the ESC to the RX because the external BEC is replacing the circuit with the same function that is inside the ESC. (Note: Sometimes this is not required but I couldn't find anything on the Novac BEC and it seems the Eiger has an internal BEC so it probably is required for your setup)

However, if your external BEC can provide a higher voltage and you want to run your higher voltage servos at a higher voltage you will have to adjust the wiring because an RX typically runs at 5v or 6v. In this case the Red wire from the ESC to the RX stays to provide the 5v/6v for the RX but the external BEC +ve red wire is removed and the servo +ve red wire is removed from their connectors that plug into the RX and the two +ve red wires are connected to provide the servo with the external BEC voltage (say 7.2v)

You don't mention an RX in your list but there should be one (little box with pins) that came with your Futaba 3pl radio. If it came with the radio it will probably already be bound to it but you may need to do that once you get the RX powered.

The cables that connect the RX to the servos and ESC have three wires usually -ve (BLACK or BROWN) +ve (RED middle) and signal (WHITE or ORANGE) Whatever colors you have make sure the signal wire goes to the signal pin on the RX and -ve and + are not reversed.

Where the battery plugs in to the ESC is usually obvious if they have the same connectors. If your battery connector does not match your ESC you will have to replace the connectors or get an adapter. Make sure you get the battery polarity correct since not all electronics have reverse polarity protection and you can destroy them.

Some ESCs need tuning. I'm not an expert on that since mine doesn't. Here's the Eiger ESC manual in case you don't have it. Much too busy a bit of paper for me to bother reading but there are probably a few things on there you need to do like set the Lipo cutoff voltage and such. There are probably TX adjustments you will need to make too

http://www.teamnovak.com/download/instructions/pdfs/55-1850-1_edge_basic_ins.pdf

 

[Trubble]

Would HIGHLY recommend looking at Holmes Hobbies or CreationFab for a 'Receiver bypass adapter'. It'll make the whole process SO much easier.


To run the BEC through the receiver,

--the ESC's and BEC's power leads both get connected to the battery connector of your choice. I use Traxxas, you use what you like.

--servo goes into channel 1

--ESC goes into channel 2, be sure to pull the red wire from this connection.

--BEC goes into any open slot.

with this setup, the BEC inside your speed control does nothing, receiver and servo are both fed by your external BEC. So long as you pull the ESC's red, the internal and external will never meet and potentially fight each other.

To run the BEC direct to the servo,

--the ESC's and BEC's power leads both get connected to the battery connector of your choice. I use Traxxas, you use what you like.

--ESC goes into channel 2, do not pull the red wire from this setup.

--BEC's output (red & black only) will go to your servo,

--black and white from servo go to channel 1 in your receiver.

with this setup, the BEC inside your speed control will feed the receiver, and the external BEC will feed the servo. Do not connect the red from your servo to the receiver, and your internal and external BECs will never meet and potentially fight each other.

*note these colors are traditional Futaba colors, your black may actually be brown, your red may actually be orange, your white may actually be yellow.