ESC question that hopefully has a simple answer.

[biggman100]

Ok, hopefully this is a simple question. Is there a rule of thumb to follow for matching an ESC to a motor. Is there a certain amp ESC to use for a specific motor? For example, what would be the best ESC for a 3650 330KV?. Or a 3650 3800KV? Or a 3660 3300KV? Or a 3660 3500KV? Or a 3660 3800KV? I just listed that many examples hoping to get a simple answer, but knowing my luck, its not that simple. This has always confused me, and every search i do tends to confuse me that much more.

 

[Greywolf74]

To me its more a question of what type of kit it is and the type of terrain its gonna be run on. The same 1/10 scale ESC that will work in a given kit on a given terrain will work for all of those motors. I personally try to buy oversized ESCs so that the ESC will run as cool as possible and last longer. For example if an 80A ESC would work then Ill probably buy a 120A to put in it but thats just me.

 

[WickedFog]

Agreed Wolf. Buggies and lighter weight 2wd vehicles don't need the same power as the bigger, heavier 4wd monster trucks and such. I don't know a lot about electronics and how all those volts, watts, amps play together, so I basically look at the ESC manufacturer's recommended uses their ESC's are good for, as they know better than I do. A lot of times, like Castle stuff, they will tell you what weight and type vehicle their ESC's are good with (buggy, truggy, 2wd, 4wd, etc). I always start here.

As @Greywolf74 said, I will usually go for a little overkill on the ESC if I can because an ESC able to handle more load than you will be pulling out of it is better than one that will struggle to supply enough current to the motor and overheat.

From there, most kits will give you a suggested motor to use. Based on that I shop for a motor in that ballpark. I also rely on videos of the kit I am working with to see how the vehicle runs, paying attention to any gearing they have tried, tires, etc, just to help narrow down on some of the guesswork if possible. Basically, I try to do some research before I drop any money.

I may even send the manufacturer an email asking their suggestions for a particular kit. Again, they generally will know better than I do what their motors will do in specific type vehicles. I make sure to give them the vehicle's scale, drivetrain, weight, and what I want out of it when I do to eliminate all the initial back and forth questions.

From there, it's all about gearing it to keep the heat below 160°F and get it running as fast as possible.

That's my routine anyway.

 

[biggman100]

To me its more a question of what type of kit it is and the type of terrain its gonna be run on. The same 1/10 scale ESC that will work in a given kit on a given terrain will work for all of those motors. I personally try to buy oversized ESCs so that the ESC will run as cool as possible and last longer. For example if an 80A ESC would work then Ill probably buy a 120A to put in it but thats just me.

Its mainly issues with two 4WD SCT's. All of my vehicles run the same WP 10BL60 ESC, but, in my 2WD SCT's, i run 3650 3300KV or 3500KV, and never have an issue, but, in my 2 4WD SCT's, i run 3660 3800KV motors, and lately, i have had issues with them acting up. I will run them for a few minutes, then have to shut them off for a bit, then they work fine until they do it again. I'm not sure if i should just get 120A ESC's, or change the motors for 3660 3300KV ones. On the one, it originally ran a GoolRC ESC that lasted 4 days, so i switched to the HW, and a month later, its starting to act the same way the GoolRC did before it completely quit.

 

[biggman100]

Agreed Wolf. Buggies and lighter weight 2wd vehicles don't need the same power as the bigger, heavier 4wd monster trucks and such. I don't know a lot about electronics and how all those volts, watts, amps play together, so I basically look at the ESC manufacturer's recommended uses their ESC's are good for, as they know better than I do. A lot of times, like Castle stuff, they will tell you what weight and type vehicle their ESC's are good with (buggy, truggy, 2wd, 4wd, etc). I always start here.

As @Greywolf74 said, I will usually go for a little overkill on the ESC if I can because an ESC able to handle more load than you will be pulling out of it is better than one that will struggle to supply enough current to the motor and overheat.

From there, most kits will give you a suggested motor to use. Based on that I shop for a motor in that ballpark. I also rely on videos of the kit I am working with to see how the vehicle runs, paying attention to any gearing they have tried, tires, etc, just to help narrow down on some of the guesswork if possible. Basically, I try to do some research before I drop any money.

I may even send the manufacturer an email asking their suggestions for a particular kit. Again, they generally will know better than I do what their motors will do in specific type vehicles. I make sure to give them the vehicle's scale, drivetrain, weight, and what I want out of it when I do to eliminate all the initial back and forth questions.

From there, it's all about gearing it to keep the heat below 160°F and get it running as fast as possible.

That's my routine anyway.

The problem i seem to run into, HW, for the ESC i use, the motor specs are listed in turns, instead of KV, so, i just made a guess as to what would work with it, based on what i saw TLR, AE, Racers Edge, and HobbyKing using. My Racers Edge Pro2 had a Wizard 60A ESC paired with a 3600KV 3650 motor, and was the first brushless vehicle i owned, and, Racers Edge originally only listed that motor and a 3300KV 3650 for that truck, so, thats where i got what i use in my 2WD SCT's from. As for my 4WD stuff, that is entirely guesswork. I bought a HobbyKing Quanam Vandal that had a HW WP 10BL50 and a 3652 3250KV, that barely has enough power to move my ECX Torment, let alone anything else that isnt a buggy. Until i bought the Vandal and an Exceed RC drift car, the Pro2 was the only vehicle i owned that was brushless. Everything else i owned up to that point was all brushed.

 

[WickedFog]

The problem i seem to run into, HW, for the ESC i use, the motor specs are listed in turns, instead of KV, so, i just made a guess as to what would work with it, based on what i saw TLR, AE, Racers Edge, and HobbyKing using. My Racers Edge Pro2 had a Wizard 60A ESC paired with a 3600KV 3650 motor, and was the first brushless vehicle i owned, and, Racers Edge originally only listed that motor and a 3300KV 3650 for that truck, so, thats where i got what i use in my 2WD SCT's from. As for my 4WD stuff, that is entirely guesswork. I bought a HobbyKing Quanam Vandal that had a HW WP 10BL50 and a 3652 3250KV, that barely has enough power to move my ECX Torment, let alone anything else that isnt a buggy. Until i bought the Vandal and an Exceed RC drift car, the Pro2 was the only vehicle i owned that was brushless. Everything else i owned up to that point was all brushed.

That's going to be the difference in a 2wd setup vs a 4wd. The 4wd is going to require more torque from the motor, and put more load on the ESC. That's why you see on the Castle stuff it tells you if it will work well with 2wd, 4wd, etc. If your motor is struggling to move the vehicle you might be running too high a pinion also.

 

[biggman100]

That's going to be the difference in a 2wd setup vs a 4wd. The 4wd is going yo require more torque from the motor, and put more load on the ESC. That's why you see on the Castle stuff it tells you if it will work well with 2wd, 4wd, etc. If your motor is struggling to move the vehicle you might be running too high a pinion also.

It doesn't struggle to move it, it just cuts out after a few minutes. As the battery gets near LVC, it does cog from time to time though. On 3S though, oddly, it doesn't have any of those issues. The issue is, i can't afford to keep buying motors and ESC's until i figure out what works.

EDIT: Right now I'm stuck between getting a 120A ESC, or a 3660 3300KV motor.

 

[WickedFog]

Is the battery you are using good? If the IR has deteriorated on it and you start getting voltage drops it will trigger the LVC in the ESC. What is the C rating on the battery? You said it runs fine on the 3s, so maybe you just have a bad 2s pack? If it runs good on 3s, why not just run it on 3s? Or are you just trying to understand what's going on for educational purposes?

 

[biggman100]

Is the battery you are using good? If the IR has deteriorated on it and you start getting voltage drops it will trigger the LVC in the ESC. What is the C rating on the battery? You said it runs fine on the 3s, so maybe you just have a bad 2s pack? If it runs good on 3s, why not just run it on 3s? Or are you just trying to understand what's going on for educational purposes?

All my batteries are Gen's Ace. Some are less than a month old, and it does it no matter which 2S battery i use. The ones i have are 5000MAH 50C, and, a friend of mine has ZEEE 5200MAH 70C batteries that are 3 weeks old, and it even does it with them. As for running it only on 3S, thats fine, except when i run with my 10 year old step-son, then its too fast for what he has.

 

[WickedFog]

All my batteries are Gen's Ace. Some are less than a month old, and it does it no matter which 2S battery i use. The ones i have are 5000MAH 50C, and, a friend of mine has ZEEE 5200MAH 70C batteries that are 3 weeks old, and it even does it with them. As for running it only on 3S, thats fine, except when i run with my 10 year old step-son, then its too fast for what he has.

Do you not have a dual rate on the throttle you could turn down?

 

[pug]

All my batteries are Gen's Ace. Some are less than a month old, and it does it no matter which 2S battery i use. The ones i have are 5000MAH 50C, and, a friend of mine has ZEEE 5200MAH 70C batteries that are 3 weeks old, and it even does it with them. As for running it only on 3S, thats fine, except when i run with my 10 year old step-son, then its too fast for what he has.

I have an Arrma Typhon 3s that I only run on 3s, it isn’t too fast on 50% speed but just fast enough for anyone to use without an issue. (If they don’t have a lead finger on the throttle.) Adjust the dual rate and you’ll be good to go.

 

[Greywolf74]

Your problem isnt the motors, its the ESCs. Buy better ESCs. you're trying to run a 45A ESC on your ECX Torment when you need probably more like an 80A or even a 120A. I wouldnt put a 45A ESC in anything bigger than a 1/16 or maybe a 1/12 scale rig. Even a 1/10 scale on road Id have at least a 60A in it, if not an 80A. I wouldnt put anything less than a 120A in a SCT or maybe an 80A is its 2WD. Just my .02

As for converting turns to kv ratings, theres no exact forumla but if you divide 43,000 by the number of turns you'll get a rough approximation of the equivalent kV rating. Example if you want to know roughly what kV a 17.5T motor is then 43,000/17.5= 2,457.14. So a 17.5T motor is about 2500kV. The formula will generally get you in the ballpark within +/-5% however as you get to the extreme ends of the spectrum (realy high or really low T motors) the margin for error increases but for most things this will work.

 

[STONER RC]

All my batteries are Gen's Ace. Some are less than a month old, and it does it no matter which 2S battery i use. The ones i have are 5000MAH 50C, and, a friend of mine has ZEEE 5200MAH 70C batteries that are 3 weeks old, and it even does it with them. As for running it only on 3S, thats fine, except when i run with my 10 year old step-son, then its too fast for what he has.

Well there's your problem man. Your running to small esc. All 1/10 should be running at least a 120amp.. should be 120amp esc all day long... the batteries you are running the 5000mah 50c can hit 250amp continuous. and the bigger 5200mah 70c one can hit 364amps continuous.. So your little 60amp esc are no match to what your running. And probably why you have a box of them in the cornner fried.. To figure out the amperage of your lipos. Take you mah x Crating= amps continuous. The problem definitely is not your motor... its your under amped esc

All my batteries are Gen's Ace. Some are less than a month old, and it does it no matter which 2S battery i use. The ones i have are 5000MAH 50C, and, a friend of mine has ZEEE 5200MAH 70C batteries that are 3 weeks old, and it even does it with them. As for running it only on 3S, thats fine, except when i run with my 10 year old step-son, then its too fast for what he has.

Are thos new lipos. Or you have always ran those 5000mah 50c.. or were you running other lipos.. your definitely under amped esc is the problem. That 60amp esc is for 1/16 and smaller. Lighter 2wd rcs not 1/10 4wd SCTs man...take a look at the article shows you how to calculate your lipos

http://learningrc.com/lipo-battery/#:~:text=For example, if you have,for short periods of time.
Here read threw this it proves. Your running the incorrect electronics. As in the esc.

https://www.eurorc.com/page/19/choosing-esc-and-motor-for-short-course--2018-edit

 

[biggman100]

Your problem isnt the motors, its the ESCs. Buy better ESCs. you're trying to run a 45A ESC on your ECX Torment when you need probably more like an 80A or even a 120A. I wouldnt put a 45A ESC in anything bigger than a 1/16 or maybe a 1/12 scale rig. Even a 1/10 scale on road Id have at least a 60A in it, if not an 80A. I wouldnt put anything less than a 120A in a SCT or maybe an 80A is its 2WD. Just my .02

As for converting turns to kv ratings, theres no exact forumla but if you divide 43,000 by the number of turns you'll get a rough approximation of the equivalent kV rating. Example if you want to know roughly what kV a 17.5T motor is then 43,000/17.5= 2,457.14. So a 17.5T motor is about 2500kV. The formula will generally get you in the ballpark within +/-5% however as you get to the extreme ends of the spectrum (realy high or really low T motors) the margin for error increases but for most things this will work.

Where do you see 45A for the ESC. All of my ESC's, at least, all of my current ones, are 60A 10BL60's.

Well there's your problem man. Your running to small esc. All 1/10 should be running at least a 120amp.. should be 120amp esc all day long... the batteries you are running the 5000mah 50c can hit 250amp continuous. and the bigger 5200mah 70c one can hit 364amps continuous.. So your little 60amp esc are no match to what your running. And probably why you have a box of them in the cornner fried.. To figure out the amperage of your lipos. Take you mah x Crating= amps continuous. The problem definitely is not your motor... its your under amped esc

Then someone should tell AE that, since their 1/10TH 4WD's run a 60A Reedy SC600 ESC, and, when the Losi Tenacity first came out brushless, that was also a 60A Dynamite Fuze ESC. Even Arrma used to send 3S trucks with only an 80A, and is currently only a 100A, and that is the one they use in all the 3S stuff. Even my Losi 22S has a 60A Dynamite Fuze paired with a 3300KV 3650 motor, so, no, they dont have to have a 120A ESC. As for the pile of burnt up ESC's i have, except for the Castle that got fried, all of those are cheap GoolRC and Surpass Hobby chinese ones. Since i bought my first WP 10BL60 RTR 2 years ago, i have only fried one of them, and that was due to my own negligence.

 

[STONER RC]

Where do you see 45A for the ESC. All of my ESC's, at least, all of my current ones, are 60A 10BL60's.

Then someone should tell AE that, since their 1/10TH 4WD's run a 60A Reedy SC600 ESC, and, when the Losi Tenacity first came out brushless, that was also a 60A Dynamite Fuze ESC. Even Arrma used to send 3S trucks with only an 80A, and is currently only a 100A, and that is the one they use in all the 3S stuff. Even my Losi 22S has a 60A Dynamite Fuze paired with a 3300KV 3650 motor, so, no, they dont have to have a 120A ESC. As for the pile of burnt up ESC's i have, except for the Castle that got fried, all of those are cheap GoolRC and Surpass Hobby chinese ones. Since i bought my first WP 10BL60 RTR 2 years ago, i have only fried one of them, and that was due to my own negligence.

What ever dude I'm done helping you. All you do is fight bit*h and mown about what is said to you... good luck

 

[biggman100]

What ever dude I'm done helping you. All you do is fight bit*h and mown about what is said to you... good luck

No, actually, i just get tired of people who constantly say the only way to do anything in this hobby is to spend large amounts of money. I have been doing RC stuff for years without having deep pockets, or spending tons to do anything.

 

[Greywolf74]

Where do you see 45A for the ESC. All of my ESC's, at least, all of my current ones, are 60A 10BL60's.

You said "HW WP 10BL50 and a 3652 3250KV, that barely has enough power to move my ECX Torment," Well the HW WP 10BL50 is a 45A ESC. So are you saying thats a typo? Even if it was a 60A ESC, thats not much better. Start running at least 80A ESCs on your 1/10 scale 2WD stuff and at least 120A on 4WD 1/10 scale and see if that doesn't make a huge difference.

Then someone should tell AE that, since their 1/10TH 4WD's run a 60A Reedy SC600 ESC, and, when the Losi Tenacity first came out brushless, that was also a 60A Dynamite Fuze ESC. Even Arrma used to send 3S trucks with only an 80A, and is currently only a 100A, and that is the one they use in all the 3S stuff. Even my Losi 22S has a 60A Dynamite Fuze paired with a 3300KV 3650 motor, so, no, they dont have to have a 120A ESC. As for the pile of burnt up ESC's i have, except for the Castle that got fried, all of those are cheap GoolRC and Surpass Hobby chinese ones. Since i bought my first WP 10BL60 RTR 2 years ago, i have only fried one of them, and that was due to my own negligence.

All manufacturers use cheap ass barely gets the job done electronics. Why do you think people tend to burn them up and replace them rather quickly the majority of the time?

No, actually, i just get tired of people who constantly say the only way to do anything in this hobby is to spend large amounts of money. I have been doing RC stuff for years without having deep pockets, or spending tons to do anything.

Its not about spending large amoutns of money. Its about buying things that will work, work properly, and last a long time so you dont have to keep spending money to replace the stuff further down the road. We had the whole huge debate about this before in that thread where you kept trying to convince Stigtheone to buy cheap electronics which you swore up and down you been using for years without issues but yet here you are in this thread wondering why half your electronics either dont work right or why they dont work at all anymore. It doesn't make sense. Does this cheap low end budget stuff work or doesn't it? You keep wanting to fly in the face of what seasoned RC hobbyists are telling you. Not just myself but others too. Its almost like your fishing for an answer that fits your warped logic on buying cheap bottom of the barrel electronics. I get why Stoner doesn't want to waste his breath anymore.

 

[WickedFog]

The whole point of this discussion is you are wanting advice on how to choose the correct electronics for your rig. Sure, there is probably a cheaper 60A ESC out there that will do what you want it to do. But the problem is, none of the guys here have used it or even heard of it. So you are never going to get guys here telling you to use something they haven't tried. So don't get upset when they recommend something they have tried and know it works.

It's never an exact science with hobbyists trying to find what works, hence the tendency to just say F it and go a bit overboard. We as hobbyists aren't sitting here with engineering degrees, calculating the weight of the rigs, and determining the exact amp loads put on the ESC based on that, the motor, gearing, etc. But the heart of the RC is the ESC, so that is the one place where you don't want to skimp.

 

[STONER RC]

The issue is, i can't afford to keep buying motors and ESC's until i figure out what works.

Ok so its has NOTHING!!! to do with deep pockets or a big cash flow. Because I have neither of those. I have common sense and I research for information about what I'm trying to do and buy for my RC.. if it was about money. I would be suggesting high end Maclan and tekin..Those two are the cream of the crop as far as electronics go. They sit on top of the electronics all by them selves.. I suggest castle because they are quality made products the WORK... AND WORK WELL.. the next one in line would be the Hobbywing products.. after those I couldn't say. Because I wouldn't waste time or money on anything less. Because they are not quality made. They might meet the spec and the price might be good. But there is always a reason why they are at a low price.. you and everyone always think it has to do with haven to spend lots of money...its about getting and buying quality equipment that works for the RC at hand weather it 2wd or 4wd. Or a buggy or SCT, or a MT. And it also mainly has to do with weight and drivetrain. Of the vehicle that the esc or electronics are going to operate... so you say you can't keep spending money on the esc/motors until you figure out what's wrong. Well with the amount of money you spent on the BOX of fried ESC's you could have bought a high end tekin or a couple castle esc's by now. And wouldn't be in the situation that your in now... hence sometimes you need to spend a little money to get quality made products. Instead of trying to save a buck. Just to throw in the BOX. at the end of the day...... so again it's about the weight and style of rc your running either 2wd or 4wd. Will tell you what esc you should be using. And yes a 60amp esc could run a 3660 3500kv motor. If it was a quality made esc. And not a cheaper rebrand chinesium made product. Some thing are worth spending a little extra money on.. think about it.... not trying to be a di*k

 

[WickedFog]

The Arrma Granite for example, running 4wd with big tires and a 100A ESC is not that big a deal because the truck by itself weighs nothing. Now if it had an aluminum chassis, metal CVD's, aluminum bracing and shock towers, that would be a whole different ballgame.

I am not familiar with the other kits mentioned that use 60A ESC's, but they are probably exactly the same - lightweight RC's.

But those ESC's have been engineered to run in those rigs - just barely, more than likely. If you pulled one of those ESC's and stuck in another rig, with more friction from the drivetrain, more weight, etc, that same ESC is likely going to overheat and die a slow death.

So... go big, or go home is I guess the best advice I can give. Face the facts. RC is not a cheap hobby. If you are buying cheap RC stuff, plan on buying more of it.