Motor perhaps overextended?

[Cyclomania]

I have a bike with a 250 watt motor.

I have overvolted this bike quite a lot. So I have a controller with max current of 25. And a 48volt battery 17AH.

When going up a slope earlier today. The motor then started making all kinds of strange noises. At least I am 80% sure this sound comes from the motor.

The battery connections still shows me 48 volts so I don't think the battery or controller have taken any damage. But the motor gave me a lot of strange sounds. It still runs but with a strange sound. Any idea what this is or how I can fix it?

 

[LewTwo]

Or perhaps go with xt90-cables might up the connection there perhaps? It is 48volt but perhaps good to go with xt90 anyway? I mean for thickness of wire and connectors.

Some time ago I switched to XT60 for all my power cables. In hind-sight, I think that Anderson Power Pole 45 Amp would have been a better choice. They are a bit larger that the Amass XT connector series but they are a heck of a lot easier to work with. They are also available with crimp (vs solder) barrels. I believe that their current capacity might be a bit underrated (particularly the silver plated variety).

Cons:
they are not water proof or water resistant
they are not available as an antispark connector

https://powerwerx.com/help/powerpole-connectors
https://www.amazon.com/dp/B07BRBRZ86



P.S. I do not disagree with Chalo regards 14 AWG ... real world experience is always better than theory.
I just happen to keep Siamese 12 AWG cable on hand.

 

[Chalo]

P.S. I do not disagree with Chalo regards 14 AWG ... real world experience is always better than theory.
I just happen to keep Siamese 12 AWG cable on hand.

I started with 12ga cable for my earliest conversions that used 20A controllers. Then switched to 10ga for 35A controllers. After a while I started doing the math and selling myself on the idea of smaller wire, because the big stuff was so stiff and obtrusive.

Now I use all those sizes depending on what I'm up against.

I will say this: 12ga wire is by far the best fit to 45A Powerpoles. So tidy. I fold 14ga wire over at the end, and trim some stands from 10ga wire to fit the same terminals. 12ga just works like you want it to.

 

[LewTwo]

[... the big stuff was so stiff and obtrusive.

I have a strong dislike for stiff cables as well. Fortunately I do not need this very often so this is what I use:

https://www.amazon.com/dp/B08MF7BN8H

I started using this because I was soldering XT connectors and the PVC insulation always melted or the cable got stiff near the solder joints. Tinned copper takes solder quickly and the silicon insulation does not melt.

Crimp connectors do not have those problems. Copper Clad Aluminum 12 AWG (PVC insulation) gives you the same size with just a very small increase in resistance over the 14 AWG copper (5% if my math is correct) and is about half the cost of 12 AWG copper. Audiophiles use it because they are dealing with high frequencies that tend to prefer the surface layer.
https://www.amazon.com/dp/B08MF7BN8H

 

[Cyclomania]

This chart says 14 gauge wire is suitable for 32 amps.
https://www.powerstream.com/Wire_Size.htm

I've used 14AWG pure copper wire for battery leads on speed controllers up to 35 amps, with no problems or noticeable warming of the wire runs. It's a rare circumstance when a controller draws its maximum power for a prolonged uninterrupted period. It's a safe bet that any one of your plugs is a much more significant bottleneck for current flow than 14ga wire is.

Hmm ok. better to resolder them again and use xt90?

 

[Chalo]

It's a safe bet that any one of your plugs is a much more significant bottleneck for current flow than 14ga wire is.

Hmm ok. better to resolder them again and use xt90?

That's not really what I was getting at. Point is, pretty much any plug presents an order of magnitude more resistance than a short run of appropriate size copper wire. My PP45 Andersons sometimes get warm enough to surprise me when they touch my leg, but the 14ga cables don't.

 

[Cyclomania]

It's a safe bet that any one of your plugs is a much more significant bottleneck for current flow than 14ga wire is.

Hmm ok. better to resolder them again and use xt90?

That's not really what I was getting at. Point is, pretty much any plug presents an order of magnitude more resistance than a short run of appropriate size copper wire. My PP45 Andersons sometimes get warm enough to surprise me when they touch my leg, but the 14ga cables don't.

I have a 48volt battery and my controller is the one in the picture below. I do think (?), that the max current of this controller is 52A. Perhaps I am thinking wrongly here but when the rated current is 26 Is not the max current supposed to be double of that?

Looks like below. Do you guys think I should go with 12awg or 14awg? Or do you call this 14ga(?)

 

[amberwolf]

I have a 48volt battery and my controller is the one in the picture below. I do think (?), that the max current of this controller is 52A. Perhaps I am thinking wrongly here but when the rated current is 26 Is not the max current supposed to be double of that?

Looks like below. Do you guys think I should go with 12awg or 14awg? Or do you call this 14ga(?)

What is the *actual* current you measure under typical loads?

What is the *actual* current you measure under worst-case loads?

 

[Cyclomania]

I have a 48volt battery and my controller is the one in the picture below. I do think (?), that the max current of this controller is 52A. Perhaps I am thinking wrongly here but when the rated current is 26 Is not the max current supposed to be double of that?

Looks like below. Do you guys think I should go with 12awg or 14awg? Or do you call this 14ga(?)

What is the *actual* current you measure under typical loads?

What is the *actual* current you measure under worst-case loads?

The current I measure going up slopes is normally around 1000-1200watts

 

[Chalo]

The current I measure going up slopes is normally around 1000-1200watts

Then it seems 26±1 amps is your controller current limit. (48V x 26A = 1248W)

 

[LewTwo]

I have a 48volt battery and my controller is the one in the picture below. I do think (?), that the max current of this controller is 52A. Perhaps I am thinking wrongly here but when the rated current is 26 Is not the max current supposed to be double of that?

Looks like below. Do you guys think I should go with 12awg or 14awg? Or do you call this 14ga(?)

What is the *actual* current you measure under typical loads?

What is the *actual* current you measure under worst-case loads?

The current I measure going up slopes is normally around 1000-1200watts

Power = 1200 Watts
Voltage (nominal) = 48 Volts DC
Current = Power / Voltage = 1200/48 = 25 Amps

 

[Cyclomania]

The current I measure going up slopes is normally around 1000-1200watts

Then it seems 26±1 amps is your controller current limit. (48V x 26A = 1248W)

Hmm ok. They were not honest then. Because I asked them about that. They told me the rated current was the stated current. So that the high current was double.

This did sound a bit strange to me when he wrote that

Do you guys think I should go with 12awg and more solid connections?

 

[amberwolf]

What is the *actual* current you measure under typical loads?

What is the *actual* current you measure under worst-case loads?

The current I measure going up slopes is normally around 1000-1200watts

That's wattage. (watts).

Current is measured in Amps.

You can calculate amps from watts, if you know the actual voltage at the moment the watts reading is taken, but that requires noting down two numbers at the same time.

It is much easier to just note down the actual Amps reading.

 

[Cyclomania]

What is the *actual* current you measure under typical loads?

What is the *actual* current you measure under worst-case loads?

The current I measure going up slopes is normally around 1000-1200 watts

That's wattage. (watts).

Current is measured in Amps.

You can calculate amps from watts, if you know the actual voltage at the moment the watts reading is taken, but that requires noting down two numbers at the same time.

It is much easier to just note down the actual Amps reading.

Hmm so perhaps it could be 52 amp controller as they say then? They claim this wattage is normal, since the motor is only 1000watts. Could that be correct?

I am not sure if my wattmeter measures amps. Should I look at this thing I have encircled in the image? During heavy loads.

 

[E-HP]

Hmm so perhaps it could be 52 amp controller as they say then? They claim this wattage is normal, since the motor is only 1000watts. Could that be correct?

I am not sure if my wattmeter measures amps. Should I look at this thing I have encircled in the image? During heavy loads.

Yes, it measures amps. A wattmeter needs current and voltage as input, although the one in your pic appears to have a rounding issue.

3.70A x 13.70V = 50.69W or rounding correctly, 50.7W not 50.6W

 

[amberwolf]

Hmm so perhaps it could be 52 amp controller as they say then?

You can eiher measure the amps, or you can calculate it from the volts and watts. Guessing what it is isn't really all that useful to you.

Always measure whenever you can, if you want to know something. Anything else is a guess of one sort or another.

If you want a guess, I agree with Chalo's calculation (which is based on an average system voltage rather than the actual voltage at the moment of your wattage reading).

But measuring will get you a real number--even a cheap meter's readings are usually better than trusting numbers provided by a seller (who has every reason to lie to get people to buy more things and give them more money).

They claim this wattage is normal, since the motor is only 1000watts. Could that be correct?

The wattage you see on the meter has nothing to do with the motor rating. A motor rating is just a number the person that rated it decided to rate it at, and often has little to do with what it is capable of, and nothing at all to do with how much power it is actually taking to operate at any instant in time.


The wattage reading on your meter has only to do with the physical load you are placing on the system (causing the motor to draw current from the controller and the controller from the battery), the controller's battery current limit, and the voltage the system sags to at that instant because of the load.

I am not sure if my wattmeter measures amps.

It likely has some instructions with it or on the website it was purchased from or it's manufacturer website that describe it's functions and usage, but generally the Amps are labelled with an A, as Watts are labelled with a W, and Volts are labelled with a V.

It may also have a "rotating" display that continuously changes between several different readings. Typically these include a Vmin, or lowest voltage the system dropped to, an Amax, or highest current the system ever drew, and sometimes a Wmax or highest wattage. It may also include an Ah and/or Wh reading of how many total Ah (amp-hours) / Wh (watt-hours) have passed thru the meter since it was last reset (or powered on), representing the capacity used out of the battery.

This manual is for a different meter (the original design of RC wattmeter that all the others are almost certainly based on), but is likely useful for deciphering yours:
https://cdn.sparkfun.com/assets/8/9/5/b/4/watts-up-dc-watt-meter-amp-meter-user-manual_v1.9.pdf
View attachment watts-up-dc-watt-meter-amp-meter-user-manual_v1.9[1].pdf

 

[Cyclomania]

i bought 4 meters of 8 awg copper car cables today.

I have also ordered some 12 awg tinned copper wire. But that one is going to take a while.

 

[E-HP]

i bought 4 meters of 8 awg copper car cables today.

Why?

 

[Chalo]

i bought 4 meters of 8 awg copper car cables today.

Why?

 

[LewTwo]

i bought 4 meters of 8 awg copper car cables today.

Why?

To beat a recently decease equine with.

 

[Cyclomania]

i bought 4 meters of 8 awg copper car cables today.

Why?

They were cheap. And I thought they might come in handy

Why not?

 

[harrisonpatm]

i bought 4 meters of 8 awg copper car cables today.

Why?

They were cheap. And I thought they might come in handy

Why not?

For a standard ebike, 8awg is crazy thick and heavy.

 

[Cyclomania]

Hmm they don't feel that heavy and clumsy actually. 8awg should at least be good for transporting current or what do you guys think?

I can always resolder it later if I am not happy with the result.

Plus I could probably do other fun stuff with this wire in the future.

But I have heard that copper that is not tinned spoils quite easily. Have any of you had that problem?

This wire is not tinned.

 

[Cyclomania]

I will say this: 12ga wire is by far the best fit to 45A Powerpoles. So tidy. I fold 14ga wire over at the end, and trim some stands from 10ga wire to fit the same terminals. 12ga just works like you want it to.

Mm I ordered 12ga when I read this. But right now I only have 8awg. And no more money until next salary. So I will try to solder this one on. Should at least do the job of transporting current right?

 

[harrisonpatm]

I will say this: 12ga wire is by far the best fit to 45A Powerpoles. So tidy. I fold 14ga wire over at the end, and trim some stands from 10ga wire to fit the same terminals. 12ga just works like you want it to.

Mm I ordered 12ga when I read this. But right now I only have 8awg. And no more money until next salary. So I will try to solder this one on. Should at least do the job of transporting current right?

It'll absolutely do the job of transferring current. With less resistance. The downsides are cost, weight, and ease of use for your application. Mostly cost. If you're fine with those downsides, then ok, there's nothing wrong with 8awg, electrically.

Myself, I can brag and say that I havr never actually purchases new wire. All the wire and cable I ever use is either salvaged from e-waste for free, or purchased for pennies from my local scrapyard. So I also frequently use wire thats larger or thicker than the current capacity that I actually need, because I'm digging through my scraps and erring on the side of caution. So no, 8wg is just fine for what you're doing. The earlier commenters are just noting that it's overkill.

 

[Cyclomania]

I will say this: 12ga wire is by far the best fit to 45A Powerpoles. So tidy. I fold 14ga wire over at the end, and trim some stands from 10ga wire to fit the same terminals. 12ga just works like you want it to.

Mm I ordered 12ga when I read this. But right now I only have 8awg. And no more money until next salary. So I will try to solder this one on. Should at least do the job of transporting current right?

It'll absolutely do the job of transferring current. With less resistance. The downsides are cost, weight, and ease of use for your application. Mostly cost. If you're fine with those downsides, then ok, there's nothing wrong with 8awg, electrically.

Myself, I can brag and say that I havr never actually purchases new wire. All the wire and cable I ever use is either salvaged from e-waste for free, or purchased for pennies from my local scrapyard. So I also frequently use wire thats larger or thicker than the current capacity that I actually need, because I'm digging through my scraps and erring on the side of caution. So no, 8wg is just fine for what you're doing. The earlier commenters are just noting that it's overkill.

Yeah I see that now. It is a bit clumsy. It was just cheap but I will save it for something else.

For the battery rail I will wait for a 12awg cable. I was lucky and found one cheaply the day before yesterday actually.

Any idea on what to do with the thick wire? Some experiment where these thick ones come in handy? Perhaps if you are building a 72 volt battery or something?