Setting motor timing w/ a multimeter
#2
Set the multimeter on amps. Some you have to move one of the leads to another port that’s for amps. Put the meter inline with your battery and connector. Remove pinion or move motor away from spur. I usually have the battery voltage around 8v. Pull full throttle and the multimeter will show the current (amps). I set mine from 5-6a. Raise can timing to increase current lower to decrease. It gets pretty sensitive so small changes are needed. Sometimes a degree or two can change the amps by quite a bit. Typically can timing ends up around 45 to 48 degrees on my motors.
Last edited by rcgod; 05-28-2020 at 07:33 AM.
#6
Tech Master
Joined: Jul 2018
Posts: 1,011
From: Florida
Doesnt KV go up as resistance goes down? you have a fixed voltage so if you put 6 amps on a lower resistance motor it spins faster. whether its comparing a 17.5 to a 17.5 or a 17.5 to a 13.5.
I think setting a motor to 6 amps is more about the thermal time constant of a motor. in english its the amount of heat a motor can dissipate continuously without overheating. its not torque and only related to kv or rpm through ohms law but its not a way to find peak power. its a way to stay under the thermal time constant.
a torque motor means it has torque at a lower rpm. that means its more efficient at a lower rpm and the gearing should be calculated to keep the average rpm on that efficiency and power peak at a lower rpm. less rpm equals less current if the resistance of the motors being compared is the same.
#7
you ask a great question that would probably add understanding to what the amp setting is actually doing.
Doesnt KV go up as resistance goes down? you have a fixed voltage so if you put 6 amps on a lower resistance motor it spins faster. whether its comparing a 17.5 to a 17.5 or a 17.5 to a 13.5.
I think setting a motor to 6 amps is more about the thermal time constant of a motor. in english its the amount of heat a motor can dissipate continuously without overheating. its not torque and only related to kv or rpm through ohms law but its not a way to find peak power. its a way to stay under the thermal time constant.
a torque motor means it has torque at a lower rpm. that means its more efficient at a lower rpm and the gearing should be calculated to keep the average rpm on that efficiency and power peak at a lower rpm. less rpm equals less current if the resistance of the motors being compared is the same.
Doesnt KV go up as resistance goes down? you have a fixed voltage so if you put 6 amps on a lower resistance motor it spins faster. whether its comparing a 17.5 to a 17.5 or a 17.5 to a 13.5.
I think setting a motor to 6 amps is more about the thermal time constant of a motor. in english its the amount of heat a motor can dissipate continuously without overheating. its not torque and only related to kv or rpm through ohms law but its not a way to find peak power. its a way to stay under the thermal time constant.
a torque motor means it has torque at a lower rpm. that means its more efficient at a lower rpm and the gearing should be calculated to keep the average rpm on that efficiency and power peak at a lower rpm. less rpm equals less current if the resistance of the motors being compared is the same.
#8
Tech Master
Joined: Jul 2018
Posts: 1,011
From: Florida
I can understand your comment. In fact its common knowledge that mechanical work adds to the heat model. My comments had nothing to do with your point and the differences and similarities between waste energy and mechanical heat, work together to create total heat but I made no connection to the concept. You quoted me making a comment from a different angle. Are you asking me a question, just talking, or did you misunderstand my comment? Google is your friend...thermal time constant, waste energy, motor efficiency. if you put 6 amps of work in without a load do the amps just disappear?
Last edited by Bry195; 06-03-2020 at 06:23 AM.
#9
I can understand your comment. In fact its common knowledge that mechanical work adds to the heat model. My comments had nothing to do with your point and the differences and similarities between waste energy and mechanical heat, work together to create total heat but I made no connection to the concept. You quoted me making a comment from a different angle. Are you asking me a question, just talking, or did you misunderstand my comment? Google is your friend...thermal time constant, waste energy, motor efficiency. if you put 6 amps of work in without a load do the amps just disappear?
I have a motor that runs hot on the track when set to 5A no load, and a different motor that runs cool on the track when set to 6A no load. No-load current draw is not a good indicator of loaded efficiency, so setting to a universal 6A no load setting for thermal reasons is not safe advice.
#10
It was a comment directed at you.
I have a motor that runs hot on the track when set to 5A no load, and a different motor that runs cool on the track when set to 6A no load. No-load current draw is not a good indicator of loaded efficiency, so setting to a universal 6A no load setting for thermal reasons is not safe advice.
I have a motor that runs hot on the track when set to 5A no load, and a different motor that runs cool on the track when set to 6A no load. No-load current draw is not a good indicator of loaded efficiency, so setting to a universal 6A no load setting for thermal reasons is not safe advice.
Setting with a multimeter? Trying to extrapolate performance based on an unloaded bench test?
Sure if all you're trying to do is waste time, go for it!
#11
Tech Master
Joined: Jul 2018
Posts: 1,011
From: Florida
It was a comment directed at you.
I have a motor that runs hot on the track when set to 5A no load, and a different motor that runs cool on the track when set to 6A no load. No-load current draw is not a good indicator of loaded efficiency, so setting to a universal 6A no load setting for thermal reasons is not safe advice.
I have a motor that runs hot on the track when set to 5A no load, and a different motor that runs cool on the track when set to 6A no load. No-load current draw is not a good indicator of loaded efficiency, so setting to a universal 6A no load setting for thermal reasons is not safe advice.
You set up a scenario with 2 different motors in 2 different applications with unmeasurable differences and ask me to solve your problem and you will tell me if im right.
Uhhh no. this sounds like your previous obsession with trying to understand motors without actually asking a question or listening and responding with yet more off topic info you grabbed from another website.
You are a smart guy. The confidence you have in your understanding is limiting you and you. Your drawn to something I say on a regular basis and I like sharing what I know with people interested. But there isnt anything for me in responding to your whatever it is directed at me.
A metal of a given size can dissipate a constant amount of heat over time. that is as simple as it gets to understand. I gave you lots of stuff to go learn if you have that kind of intention. efficiency is a percent of what? the key word being percent.
Its ok if you think Im wrong but Im going to ask you to explain why. But if you want me to support my comments stick to the subject or ask a question about the new topic you are introducing. There is nothing in it for me to take a random statement from someone who clearly has what they believe to be an answer and isnt willing to have a fair dialogue. I dont think there will be anything in it for you either.
Last edited by Bry195; 06-04-2020 at 08:56 PM.
#12
Ok lets review the situation. You direct a comment at me that has nothing to do with my comment.
You set up a scenario with 2 different motors in 2 different applications with unmeasurable differences and ask me to solve your problem and you will tell me if im right.
Uhhh no. this sounds like your previous obsession with trying to understand motors without actually asking a question or listening and responding with yet more off topic info you grabbed from another website.
You are a smart guy. The confidence you have in your understanding is limiting you and you. Your drawn to something I say on a regular basis and I like sharing what I know with people interested. But there isnt anything for me in responding to your whatever it is directed at me.
A metal of a given size can dissipate a constant amount of heat over time. that is as simple as it gets to understand. I gave you lots of stuff to go learn if you have that kind of intention. efficiency is a percent of what? the key word being percent.
Its ok if you think Im wrong but Im going to ask you to explain why. But if you want me to support my comments stick to the subject or ask a question about the new topic you are introducing. There is nothing in it for me to take a random statement from someone who clearly has what they believe to be an answer and isnt willing to have a fair dialogue. I dont think there will be anything in it for you either.
You set up a scenario with 2 different motors in 2 different applications with unmeasurable differences and ask me to solve your problem and you will tell me if im right.
Uhhh no. this sounds like your previous obsession with trying to understand motors without actually asking a question or listening and responding with yet more off topic info you grabbed from another website.
You are a smart guy. The confidence you have in your understanding is limiting you and you. Your drawn to something I say on a regular basis and I like sharing what I know with people interested. But there isnt anything for me in responding to your whatever it is directed at me.
A metal of a given size can dissipate a constant amount of heat over time. that is as simple as it gets to understand. I gave you lots of stuff to go learn if you have that kind of intention. efficiency is a percent of what? the key word being percent.
Its ok if you think Im wrong but Im going to ask you to explain why. But if you want me to support my comments stick to the subject or ask a question about the new topic you are introducing. There is nothing in it for me to take a random statement from someone who clearly has what they believe to be an answer and isnt willing to have a fair dialogue. I dont think there will be anything in it for you either.
And I'll reiterate my reply. An arbitrary 6A no load setting is no guarantee that it won't overheat. Some motors overheat well before then. I'm not asking you a question or for a solution to a problem, nor am I trying to understand how motors work. I'm telling you that this statement of yours that I quoted is not accurate. Following that advice will destroy certain models of motors.
#13
Tech Master
Joined: Jul 2018
Posts: 1,011
From: Florida
I highlighted the part of your comment in bold that I was specifically referring to in my original reply. I'll quote it again if it helps.
And I'll reiterate my reply. An arbitrary 6A no load setting is no guarantee that it won't overheat. Some motors overheat well before then. I'm not asking you a question or for a solution to a problem, nor am I trying to understand how motors work. I'm telling you that this statement of yours that I quoted is not accurate. Following that advice will destroy certain models of motors.
And I'll reiterate my reply. An arbitrary 6A no load setting is no guarantee that it won't overheat. Some motors overheat well before then. I'm not asking you a question or for a solution to a problem, nor am I trying to understand how motors work. I'm telling you that this statement of yours that I quoted is not accurate. Following that advice will destroy certain models of motors.
“And I'll reiterate my reply”
Your comments still have nothing to do with me. If you havent asked a question and dont understand my comment....I can suspect what you want but Im not going to participate in a topic that I wouldnt even get the satisfaction of learning or teaching something.
“An arbitrary 6A no load setting is no guarantee that it won't overheat. Some motors overheat well before then.”
I referenced the method for context. I didn’t recommend anything. You made comments that I indicated a current setting has something to do with total heat. I didnt but it does. You can ask a question or move on.
“I'm not asking you a question or for a solution to a problem, nor am I trying to understand how motors work”
That’s good for me but I would recommend you do.
“I'm telling you that this statement of yours that I quoted is not accurate. Following that advice will destroy certain models of motors.“
You misunderstand. You can reevaluate my comments now that Ive told you a couple times you dont understand. Ask questions or accept your understanding.
Last edited by Bry195; 06-05-2020 at 06:43 AM.
#14
in all honestly I have seen Bry195's motors at the track he tunes them pretty much perfect!! they are super fast (honestly probably the fastest motors at our track) they always come off the track ice cold



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