ESC ESC Crash Course

StageMage

New Member
Hi! I’m brand new to this forum, and fairly new to the RC hobby as well. I need a quick crash course in ESCs. I’m trying to keep my ‘ol conquest alive, and the part failing this time is the stock ESC. I need a new one, but since Helion is long gone, I don’t know what to get/what will work in my truck. I’m using the stock krypton receiver and a traxxas 550 12t Titan brushed motor. But I don’t know what the a rating means. The manual says the stock ESC is 40a. What does that mean? Are there any other measurements I need to know about for comparability with a new ESC? Also, if I’m posting this in the wrong place, please let me know where to move it to!
 

RandyDSok

Well-Known Member
40a is 40 amps... ie the max burst amperage the ESC can handle. Voltage is another aspect you'll need to know as is whether it's for a brushed ( as you stated ) or brushless motor. Brushed ESC's/motors use 2 wires and brushless ones use 3 wires going to the motor from the ESC. Size is the last aspect you must consider so what you get isn't too large for the location it is placed in.

Additional info... burst amperage is the amount of current the ESC can handle for just a few seconds as apposed to continuously ( which is lower ) which would be better to know but few ever list it.
 

StageMage

New Member
So would there be any reason to change the amps? Or should I simply look for another 40 a? And then when you said voltage, is that just the rate of the battery discharge I’m using that the ESC can handle?
40a is 40 amps... ie the max burst amperage the ESC can handle. Voltage is another aspect you'll need to know as is whether it's for a brushed ( as you stated ) or brushless motor. Brushed ESC's/motors use 2 wires and brushless ones use 3 wires going to the motor from the ESC. Size is the last aspect you must consider so what you get isn't too large for the location it is placed in.

Additional info... burst amperage is the amount of current the ESC can handle for just a few seconds as apposed to continuously ( which is lower ) which would be better to know but few ever list it.
 

RandyDSok

Well-Known Member
I'm going to provide a quote of a reply I gave to another user and I'll include some stuff you didn't ask about since it can also apply to your situation even if it isn't an airplane... this user is/was trying to increase flight time, in your case it'd apply to run time.


Think of it like this... You can relate electricity to water to get a handle on it in your head.

Voltage - is pressure for electricity... like pressure is to water.

Amperage - is the current... or amount of flow. The more water that passes a point, is the same as the amount of electricity ( MAH in batteries ) that flow.

Wattage - is the amount of work that can get done by either water or electricity.

Resistance - ie friction ... with electricity, it's the lost energy to heat.


The MAH or AH ( depending on how you want to measure it ) is the amount of stored energy, waters analogy would be the water tank. The faster the electricity flows, the quicker you drain the tank. You can increase the flow by opening the throttle wider, or decrease it by closing it. You can also increase the flow by using a bigger pipe ( large C value ) or decrease it by using a smaller pipe ( smaller C value ). So lowering the throttle has the same end result as lowering the C value, it slows down the flow or current depending on which word you want to pick.

As we increase our throttle on the radio... the resistance values also increase so it becomes less efficient at some point along your throttle curve. So the trick to extending the flight time... is to find where the sweet spot on the throttle is at for your given battery and motor. It seemed on most of my airplanes, the sweet spot seemed to be in the 60%-80% range on my throttle... but it varied depending on which airplane I was flying at the time as well as the flight conditions.

To find your sweet spot requires a few test flights with each one using a different spot on the throttle and flying for the same amount of time each time. Then just see how many MAH you put back into the battery for each flight.
 

RandyDSok

Well-Known Member
Oh... and for the question about going for a larger amperage... sort of depends on the price of the ESC as to whether or not it'd matter. I'd assume the 40a one was matched to the expected use they considered, so it's unlikely to gain you much. You'd also end up with a larger ESC which may not fit in the space it allows for in the vehicle.
 

StageMage

New Member
Oh... and for the question about going for a larger amperage... sort of depends on the price of the ESC as to whether or not it'd matter. I'd assume the 40a one was matched to the expected use they considered, so it's unlikely to gain you much. You'd also end up with a larger ESC which may not fit in the space it allows for in the vehicle.
Cool! Thank you so much!
 

D.O.G.

Goblin 380 Supporter
I'm going to provide a quote of a reply I gave to another user and I'll include some stuff you didn't ask about since it can also apply to your situation even if it isn't an airplane... this user is/was trying to increase flight time, in your case it'd apply to run time.
Hey...that sounds familiar :shhh:
 
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