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#1
Okay, with the Guinea Pig you use a Y-power harness from the batteries to the ESC's. Build a C-130 that size, but it has 4 motors, thus four ESC's. So, 3 Y-power harnesses? Can it be that simple?
Now, how do you get longer times in the air, and... well... a touch more oomph from the motors? Build some Series harness between two 5500 mah 3 cells?
Even though I do remember some high school electrical stuff, at my age I have to look up and calculate formulas I haven't worked with in... well, let's say awhile. A long, long, long... while.
 

ElectriSean

Eternal Student
Mentor
#2
The typical Y harness is a parallel connection, red to red, black to black. Loads connected in parallel all receive the same voltage. Batteries connected in parallel also give the same voltage as 1, but the capacity of the batteries is added. Connecting batteries in series increases the voltage, it becomes additive while the capacity remains the same.

Connecting 2 3S batteries gives you a 6s (22.2v), which is probably more than your motors and ESC's can handle.
 
#3
Thank you @ElectriSean ! Okay, so from the battery bay to the 4 motors I'll need 3 Y-harnesses, so it looks like a tree. Second, I've heard it is better to use a higher mah single battery than parallel two or more. Let me draw up a quick diagram to make sure I have this right.
 
#5
First configuration is something like this.
View attachment 121122
4 motors, 4 ESC's, and 3 Y-Harnesses. But if I need/want more power for longer flights...
Electrical Layout 4 Motor 4 Channel-2.png
4 motors, 4 ESC's, 4 XT-60 Y-Harnesses, 2 3S 45C 5500 mAh Lipo Batteries?
Next question if this is right, do you hook into power from either battery to the receiver? Could I then use the receiver plug off the second battery to run... say... a light kit?
 
#7
And speaking of light kits...
Okay, I've got channel 7 of my setup as my light kit, that is switchable for landing-runway-taxi lights. Can't I set up this channel on my transmitter with a three position switch to be All Off, Main On, All On?
 

ElectriSean

Eternal Student
Mentor
#9
Next question if this is right, do you hook into power from either battery to the receiver? Could I then use the receiver plug off the second battery to run... say... a light kit?
Usually the receiver is powered by a BEC on the ESC, not many receivers can handle full battery voltage and prefer 5-6V. Another advantage of a PDB such as the one I linked is that is has a 5V BEC as well, so you could use cheaper ESC's that don't have one.

So, Y harness batteries to hub, each ESC to hub, receiver, light kit, to hub?
Correct.

And speaking of light kits...
Okay, I've got channel 7 of my setup as my light kit, that is switchable for landing-runway-taxi lights. Can't I set up this channel on my transmitter with a three position switch to be All Off, Main On, All On?
Depends on the light kit, do you have a link?
 
#10
Usually the receiver is powered by a BEC on the ESC, not many receivers can handle full battery voltage and prefer 5-6V. Another advantage of a PDB such as the one I linked is that is has a 5V BEC as well, so you could use cheaper ESC's that don't have one.



Correct.



Depends on the light kit, do you have a link?
https://www.amazon.com/dp/B07DK8MN2N/?tag=lstir-20
Currently unavailable, but I have two.
 
#11
I guess what I meant was, can't you tell the receiver to shut power off to an auxiliary channel?
And that Power Hub looks to be the way I need to go. Planning on a Hercules build. A Power Hub like this one, even though it will take a bit of soldering, will be the way to go.
So then, Battery Alarm and Lost Aircraft Alarm would also direct to Power Hub?
 
#12
And I always wondered. Battery Alarms have two red number LED's to set/count down voltage. Couldn't there be a Green, Amber/Yellow, Red bright output LED's or one of those RGB units that you could poke out somewhere near the bottom, and just see the condition of your power?
 

ElectriSean

Eternal Student
Mentor
#13
I guess what I meant was, can't you tell the receiver to shut power off to an auxiliary channel?
And that Power Hub looks to be the way I need to go. Planning on a Hercules build. A Power Hub like this one, even though it will take a bit of soldering, will be the way to go.
So then, Battery Alarm and Lost Aircraft Alarm would also direct to Power Hub?
The receiver doesn't control the + and - rails, all those pins are connected in parallel. The signal pin is the only thing connected to the channel individually. This is a PWM signal that is used to control the position of servos. The light kit is controllable by PWM signal, but you'll have to refer to the manual to get it set up the way you want. I would be surprised if it couldn't use a 3 position switch.

Battery alarms are usually connected to the balance lead on the battery, this allows them to see the individual cell voltages.
 
#14
I got this as a screen shot from the Matek add on Amazon.
Matek Power Hub Connections.png
Okay? Is this the configuration for a Quad? The RX says CPPM RX, and it +/-/Signal out to a... Flight Controller? And what is an OSD? Is that like a Eagle HUD unit?
 
#15
The receiver doesn't control the + and - rails, all those pins are connected in parallel. The signal pin is the only thing connected to the channel individually. This is a PWM signal that is used to control the position of servos. The light kit is controllable by PWM signal, but you'll have to refer to the manual to get it set up the way you want. I would be surprised if it couldn't use a 3 position switch.

Battery alarms are usually connected to the balance lead on the battery, this allows them to see the individual cell voltages.
PWM = Pulse Wave Modulation? I used to work with PCM = Pulse Code Modulation systems in the Army.
Plan to put Master External Power Off Switch on all my birds. Is and where would you hook one up with the Power Hub?
 

Hai-Lee

Old and Bold RC PILOT
Mentor
#16
I guess what I meant was, can't you tell the receiver to shut power off to an auxiliary channel?
And that Power Hub looks to be the way I need to go. Planning on a Hercules build. A Power Hub like this one, even though it will take a bit of soldering, will be the way to go.
So then, Battery Alarm and Lost Aircraft Alarm would also direct to Power Hub?
There is a way to switch power using a Rx channel but I only know the old school method.

Use a "Brushed ESC" in the Aux channel and connect the output to a Relay, (I did say old school). The relay can switch high current up to the contact ratings of course.

Its old tech but it worked well!

Have fun!
 

ElectriSean

Eternal Student
Mentor
#17
That configuration is for a quad, but it would be very similar for a plane. Just eliminate the pieces you aren't using, like the flight controller and FPV system. OSD = On screen display, which is a text overlay on the FPV feed with information like battery voltage etc, provided by a FC or external sensors. CPPM is Combined Pulse Position Modulation, which allows up to 8 channels on a single signal wire. It used to be common on multirotors (cleaner wiring to the FC) , but isn't used much on planes as the receiver usually directly controls the servos.

PWM = Pulse Wave Modulation? I used to work with PCM = Pulse Code Modulation systems in the Army.
Plan to put Master External Power Off Switch on all my birds. Is and where would you hook one up with the Power Hub?
PWM = Pulse Width Modulation - https://en.wikipedia.org/wiki/Servo_control

As for an external power switch, the only way to truly kill the power is to break the battery connection before the PDB. This would be a fairly heavy duty switch, which isn't really necessary - you can just disconnect the battery.
 
#18
There is a way to switch power using a Rx channel but I only know the old school method.

Use a "Brushed ESC" in the Aux channel and connect the output to a Relay, (I did say old school). The relay can switch high current up to the contact ratings of course.

Its old tech but it worked well!

Have fun!
That's how, or close to my first nav light set up on a friends bird years ago. Replaced the relay with a automotive (Asian light duty) flasher. That output ran the top and bottom flashing red lights. This was Pre-LED's, so your options were automotive marker lights or wheat grain bulbs. I used marker lights. Added point. This bird had enough poop to run a tiny 12v generator (converted brushed motor) off the drive shaft, with a tiny sealed bike battery for electrical. Long as you had gas you had electrical, and then about ten minutes after motor died. Last I heard everything worked great until his RX lost the antenna at a challenge meet. In those days you didn't have "Safety Programs" in your RX package, so she just leveled out and keep going... Found a week later crashed into the top of a barn. Ran out of fuel and glided in. The farmer told him he thought it was a real full sized plane with engine trouble until it hit the barn. As you'd expect it was toast.
 

Hai-Lee

Old and Bold RC PILOT
Mentor
#19
That's how, or close to my first nav light set up on a friends bird years ago. Replaced the relay with a automotive (Asian light duty) flasher. That output ran the top and bottom flashing red lights. This was Pre-LED's, so your options were automotive marker lights or wheat grain bulbs. I used marker lights. Added point. This bird had enough poop to run a tiny 12v generator (converted brushed motor) off the drive shaft, with a tiny sealed bike battery for electrical. Long as you had gas you had electrical, and then about ten minutes after motor died. Last I heard everything worked great until his RX lost the antenna at a challenge meet. In those days you didn't have "Safety Programs" in your RX package, so she just leveled out and keep going... Found a week later crashed into the top of a barn. Ran out of fuel and glided in. The farmer told him he thought it was a real full sized plane with engine trouble until it hit the barn. As you'd expect it was toast.
Thanks for the mental picture and the laugh that was a result.

Have fun!
 
#20
That configuration is for a quad, but it would be very similar for a plane. Just eliminate the pieces you aren't using, like the flight controller and FPV system. OSD = On screen display, which is a text overlay on the FPV feed with information like battery voltage etc, provided by a FC or external sensors. CPPM is Combined Pulse Position Modulation, which allows up to 8 channels on a single signal wire. It used to be common on multirotors (cleaner wiring to the FC) , but isn't used much on planes as the receiver usually directly controls the servos.



PWM = Pulse Width Modulation - https://en.wikipedia.org/wiki/Servo_control

As for an external power switch, the only way to truly kill the power is to break the battery connection before the PDB. This would be a fairly heavy duty switch, which isn't really necessary - you can just disconnect the battery.
I like to have a "Master Off Switch" just because of... well, old habits after some nasty "Oops I bumped the sticks!" incidents on the flight line. And I'm not keen about having to open the main wing or pull off the nose out there either. Takes time from another pilot, since the fields I fly at don't let you roll out to the flight line or roll into the prep line under power.
Read the Wiki link you posted. Cool on the Pulse Width Modulation. Makes more sense now. BTW I play to use a FPV with an Eagle OSD (On Screen Display-Duh!). And possibly a Cam-Switcher. I want a Look Down Cam I can switch to, or export to a monitor at my ground station. I've seen 3-way switchers, so I could do bottom cam (near nose), and cargo cam internal.