BananaHobby RC Repair Guides:
Basic Radio Wiring Guide: ESC and Battery

 This guide will cover the basics as well as the most important points in regards to hooking up your ESC and Battery.

 For demonstration purposes, a 4 Channel Radio System will be used as well as an ESC unit with an External BEC attached.

 Some of the equipment or parts you have may not look like the units shown here but the basics that are covered here will still be applicable.


 In this picture, you can see the 4 Channel Transmitter Controller with the throttle stick and throttle trim tab set at "0" value. This is the standard position for the Radio Systems to be in at the resting and startup stages.


 Here, we have circled in red, for your convenience, the location of the throttle control stick and throttle trim. They MUST be at these positions for the plane to properly start up.


 This is an example of a standard receiver unit. It is possible for the manufacturers to label the channels on the receivers in numbers or with abbreviations, as seen here.

  Please note the channel labeled as "Batt" does not stand for battery, but for Battery Eliminator Circuit.



 Here is an example of an Electronic Speed Controller (ESC) unit with an External Battery Eliminator Circuit (BEC) attached.

 Your ESC may or may not have an external BEC attached, but it will have a throttle servo lead wire as well as a battery input wire. As previously noted, the battery is never connected to the receiver. It is connected to this ESC unit via the battery input wire. Sometimes the BEC will come from the ESC instead of the battery wire, like this one.

 The power is sent from the ESC to the receiver by means of the throttle servo lead wire, which not only supplies power to the receiver and other servos/functions plugged into the receiver, but is also responsible for the throttle control from your transmitter controller.


 Here is a closer look at the three wires we had just discussed. Note the green ring-shaped object attached to the BEC wire. Almost all external BECs will have that attached; which is a good method for differentiating between the BEC and throttle wires.

 Also, please take note of the servo lead connecters shown here. On one side, you can see that they have some copper contacts exposed while the other side is all black plastic. It is important that you note which direction you have the copper contacts facing when plugging into the receiver.


 Now we attach the BEC to the "BATT" channel, and the Throttle wire to the "THRO" channel. Please note, sometimes the "BATT" channel can be labeled as "BAT" or with a simple arrow pointing to the pins. The "THRO" channel could also be labeled "THR" or with a channel number which will most commonly be Channel 3.

 As previously noted, it does matter which way you have your servo lead connecters plugged in. You will want the side with the copper contacts exposed, facing up. What that means is if you position your receiver the same direction as the label on the receiver is positioned and you can read all of the channel listings, you would consider the top part of the receiver as facing "up". This photo shows a receiver positioned correctly and the servo lead connecters plugged into it have their copper side facing "up".


 Here we see a closer view of the wires coming from your Li-Po battery.


 This is called a Deans type connecter. This is what plugs into your ESC to supply power to it and, subsequently, the rest of your aircraft. Please note, sometimes other connecters, such as bullet connecters, may be used on the ESC and Battery.

 This is a 4-pin connecter mean for connecting your battery to a battery charger. The pin numbers can tell you how many cells a battery contains. Subtract one for the ground wire and count each remaining pin as one cell. This battery is a 3 cell Li-Po.

 In the past, some people have, mistakenly, believed that this plug is meant to go into the receiver. Once again, UNDER NO CIRCUMSTANCES SHOULD YOU EVER PLUG THE BATTERY DIRECTLY TO THE RECEIVER UNIT!


 Now that you have your ESC plugged in properly, the only thing left is to turn on the transmitter first, and then plug in your battery.


 Remember to always turn on the transmitter before plugging in the power to your ESC if it is hooked up to your receiver. The rule of thumb is the transmitter should already be ON whenever the receiver is powered. This means the transmitter will be the first thing you turn on at the power up stage and last thing you switch off at power down stage. Failure to do so could allow your receiver to pick up stray signals and possibly cause damage to your radio, electronics, or aircraft.


 Connect your Battery to the ESC, as shown here, and you are done! Your ESC should now be hooked up to your receiver. On your aircraft, this would mean, you should have throttle control at this time.

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