I'm building my first electric plane and have problems with speed controllers. One battery is powering the receiver, servos, and motor. The first speed control (E-Flight 10A) worked for one flight but afterwards there was very weak power to the servos.

A second speed control was bought (E-flight 10A pro) but this speed controller causes the motor to stutter and shutoff after several seconds. I've tried programming it every way and it still does it. I'm not sure what's wrong. I'm been using a fully charged battery but it's like the low voltage shut off is always being triggered.

Trasky,
You may want to repost this in the electric flight forums, the folks here might not have nearly the same amount of EFlight knowledge as over there. Most people here fly glow. Good luck, I hope you can get your question answered.
Curtis

When you say "one battery is powering", does that mean you have two battery packs per chance? Your post sort of implies that you have two packs. But, most likely, you have one battery pack.

What you have to do is determine several things:

1. If you have the right battery pack for what you are planning to do (amp-hours, voltage, and composition (LiPo, NiMH, whatever).

2. If you have the right ESC that matches the plane weight with the current draw you are going to encounter in normal flight.

3. If you have the right motor that matches all of the above.

There is a weight/power ratio that is compatible with your electric plane setup and flight style (normal flight, agressive flight, or 3D). You have to make sure that for the given weight (combination of all components.. airframe, servos, ESC, motor, and battery) and flight style, will work with the motor/ESC/battery pack you have chosen.

It's not as easy as you may have been led to believe. You may have burned up either the motor or the ESC. You have to do your homework to make sure you have the right combintatoin.

CGr.

As C G retired stated the various components must be properly matched. You did not say what plane motor etc you are useing. Only that you are useing a 10A speed control. That is a very minimal speed control so it may be your problem. There are many facts provided here in RCU. I suggest you do some research on what you need.

Battery is 7.4 V - 800Ah, motor suggested voltage is 7.2V-8.4V or 270-600mAh, and both speed controllers are 10A.

The speed controller provides power to the reciever for the servos. You do not need a separate battery. If you have simply plugged the connector from the speed controller into the reciever, as well as plugged a second battery into the reciever, that might be causing your problem. The output voltage from the ESC to the reciever is probably slightly lower than the voltage being provided by the second battery, which may be playing heck with your signal to the ESC. Try it without the second battery.

Brad

Do the ESC's have a BEC ?


Bob

Your speed control has the default voltage cutoff set for a 3 cell batterie you need to change it to match your batteries if you are using 2 cell lipos with the 3 cell setting
your speed control will cut off power so that it doesnt draw your batteries down to low and kill them. see the instructions that came with your speed control so your ESC is set up for the right voltage cut off

If you need to you can down load a copy from the Eflite web site.

Note set the throttle trim all the way down before setting up your speed control

I copied part of the manual below.

The default settings (from the package) for your
E-flite 10-Amp Pro ESC are as follows:
• 3S (9V) auto cut-off for Li-Po
• Brake Off
• 4-pole and greater timing (outrunner or 6-pole motors)
• Throttle input range set to Auto Select Mode
(1.2ms-1.8ms)

Entering the Programming Mode
1. With the battery disconnected from the controller, and the transmitter
turned on, first move the throttle stick to full throttle (>1.7ms)
position. Leave it in this position and then connect the battery to the
controller.
2. Wait for 5 seconds, and the ESC will give two sets of fast ringing tones
to indicate you have successfully entered the programming mode.
3. Once you hear these tones, move the stick to center (between 1.4 and
1.6ms), and the controller will beep 1 time, this indicates menu item 1
4. The controller will now wait 5 seconds for you to make your selection;
your programming options are either full throttle (>1.7ms), or idle
(<1.3ms).
5. When you have made a valid selection the control will beep once with
a lower tone, and you can move the stick back to center for the next
menu item (2 beeps, 3 beeps and so on). If you do not make a
selection within 5 seconds, the controller will move to the next
menu item.
6. Please note that if you do not need to program every menu item, you
can simply exit the programming mode after you have made the
required selections. You can do this by moving the throttle stick
straight to Idle, after making your selection, or leaving it in the Idle
position if you made a no selection (for approximately 8 seconds), until
you hear one set of 3 medium length rising tones that indicate the
controller has armed the motor, or by simply unplugging the battery.

Programming Menu 1 – Voltage Cut-off
Use this option to set the voltage at which the controller will shut down
the motor to prevent damage to your battery, when it reaches the cut-off
voltage. You will know that your battery pack has reached auto cut-off
when you hear the motor “pulse” repeatedly.
1. 3S Li-Po voltage cut-off – Full Throttle
2. 2S Li-Po or Ni-Cd/Ni-MH voltage cut-off – Idle
3. 70% Smart Cut soft cut-off (See below for Smart Cut information)
NOTE: To access the 70% Smart Cut option, leave the stick at full throttle for 7 seconds while in menu
item 1, until 7 beeps are heard, then continue through the program normally. This option will activate the
soft cut-off at 70% of startup voltage. For example, if your pack measures 10.0 volts at startup, then the
soft cut will occur at 7.0 volts. The Smart Cut option will check the startup voltage every time you plug the
battery into the controller, so beware of using partially charged packs, as the system cannot protect your
Li-Po batteries if you are using Smart Cut and connect a partially charged pack.
You will know your battery pack has reached soft auto cut-off when you
hear the motor “pulse” repeatedly. We recommend you land your model as
soon as you hear the motor pulse (indicating the pack voltage has dropped
to the cut-off voltage level) to prevent over-discharge of the Li-Po battery
pack, and to prevent sudden power loss.