Motor Now Cutting Out......??

[camebeloc]

Hey Gang

A techie question if I may from this 'electrical newbie'.

I have now an issue after ONLY upgrading my power system from 48/20 SLA to 60/20 Lithium, hoping someone can help with any info...

First what I rode two season's ago:

500(800w peak) ebike (scooter type emmo brand)
Has the delta wye mod done(2nd gear on switch added)
72 v controller
48 v/20a SLA

Bike ran great all season, with a top speed of about 58-60 km/hr....

Then this season I upgraded only one thing...power:

The ONLY THING I CHANGED was to lithium polymer using a common HK upgrade many here have done....(16 HK Turnigy 4s 5000 mah in series/parallel to make 60v/20ah)

And now the problem:

Since doing the lithium upgrade and again IT ONLY, the bike when it hits about 52-54k ALWAYS the motor will cut out, I have to 'release the throttle and then come back on it' to get power again, but it now can't seem to get past about 54k when the ole 48/20 SLA setup was doing almost 60k

Doesn't make any real sense to me, as I now have MORE power.......no?

I have:

-Checked all connections to controller etc

-Checked brake levers thinking maybe cutout was from them at higher speed

-Even checked the delta/phase wires and connections all seems fine

-And knowing lithium being an rc guy for years.... I checked ALL cells and the pack is aok & balanced......

Any idea's why this cutout is happening?

Anything else to check or to any info would be greatly appreciated....


Cheers and thank you in advance....

 

[dogman dan]

Maybe this thread just didn't get seen yet.

First question is exactly what have you done with the lipos, how are they connected, and how are you charging them. You say HK, lithium, so I'm assuming the 20c hardcase lipo. (lico)

Second question is what the controller is, is it stock, or did you buy a 72v controller.

I'm still stumped at the moment, because it sure shouldn't be a battery issue. About all I can think of at the moment, is you don't really have them wired to 60v, and are actually running 44v, but I would guess you confirmed your voltage with a meter at some point.

If it was a throttle issue, I would expect the cut out to happen immediately on rolling on full throttle, not only when you reached a certain speed.

 

[Ykick]

Pictures speak 1,000 words.

Best I can offer is that cutout and restore via throttle is often an over current condition. Changing to RC Lipoly I can assure you that the system is seeing much higher peak current A than on the old SLA.

60V? What is the series configuration? 16S? That's closer to 67V off the charger. You said it was 72V controller so that shouldn't hurt anything. But, the peak current can and will be much higher than the old battery system.

Perhaps a bad connector? 'Wouldn't be the 1st time....

Unless you have some really bad RC Lipoly it should NOT be voltage sag causing this behavior.

 

[dnmun]

what is the current flowing when the controller cuts out? what was the current when you used the SLA? you did not include that data.

 

[dogman dan]

This is where my ignorance shows a bit. Others that know controllers better might know if yours has an overcurrent cutoff. It's quite possible you are bumping into something like that, since the lipo should be providing you with more power in the form of higher voltage under load.

But I'm still confused. Wouldn't it have taken more wattage to reach the higher speeds he was getting with sla? So why didn't it happen then.

I'm thinking perhaps it's one of those more random things you see with cars sometimes. Change the brake pads, and then the tire starts thumping that very day. It's the tire, but why it started the instant you changed the brake pads is just a mystery.

Controller is just going bad is my guess at the moment. Nothing to do with the battery, 60v into a 72v controller should be fine. One last guess, is the controller getting any cooling air?

 

[camebeloc]

Maybe this thread just didn't get seen yet.

First question is exactly what have you done with the lipos, how are they connected, and how are you charging them. You say HK, lithium, so I'm assuming the 20c hardcase lipo. (lico)


yes, 20 c Hardcase from hk is right, and yes, wired right, pack is bulk charged to yes voltage confirmed, full charge is 67.2 v dogman..., and balanced with bulk paralelel cable,,,all lipo is fine and test aok....

Second question is what the controller is, is it stock, or did you buy a 72v controller.

my fiend(who is no longer around) put in this 72 v 'china' controller, sorry no make or model or spec info, but again, * this 72 v controller was in the 48/20 SLA setup, so doubt its that......

I'm still stumped at the moment, because it sure shouldn't be a battery issue. About all I can think of at the moment, is you don't really have them wired to 60v, and are actually running 44v, but I would guess you confirmed your voltage with a meter at some point.

yes red to black 'of next' for 4 in row, and 4 rows= 16 lipos in all, 4s 5000 making 67.2 v top charge....

If it was a throttle issue, I would expect the cut out to happen immediately on rolling on full throttle, not only when you reached a certain speed.

answers above in italic dogman,,,thnx!

yea me too, could the throttle have one TINY bad spot on it? no hang on, it was fine with the 48/20 sla

THis issue must be related to the lithium somehow!

got ya stumped eh guys? lol, appreciate the help, onto the next post,,thnx so much dogman for trying to help me!

 

[camebeloc]

Pictures speak 1,000 words.

Best I can offer is that cutout and restore via throttle is often an over current condition. Changing to RC Lipoly I can assure you that the system is seeing much higher peak current A than on the old SLA.

60V? What is the series configuration? 16S? That's closer to 67V off the charger. You said it was 72V controller so that shouldn't hurt anything. But, the peak current can and will be much higher than the old battery system.

Perhaps a bad connector? 'Wouldn't be the 1st time....

Unless you have some really bad RC Lipoly it should NOT be voltage sag causing this behavior.

thanks ykick for also chiming in with the info...... and yes yer rite and seen above to dogman, its 67.2 v and yes 16s fully charged and in a 72 v controller should be fine


and have used turnigy lipo for years flying rc and THINK its aok quality same in hardcase packs.....but as I said to dogman, may try next time to put medic on or run a cell alarm to see if their may be 'a drop' in power somewhere...

ya were all stumped so far.....and will AGAIN check all the connectors, but why would it all run up to 54, and its ALWAYS the same speed usually 54 k......

thnx mate for trying,,,,really appreciated!

 

[camebeloc]

what is the current flowing when the controller cuts out? what was the current when you used the SLA? you did not include that data.

thnx dnmum for also chiming in,,isn't this fun?

a doorprize for the one that gets the answer!!! lol

bro, aagin, newbie with limited electrical experience, a guy did the mod for me and is long 'gone'

HOW would I check such a thing to provide you this answer? I don't own a tester, just the HK medic is what I use to check my lipo's occasionally or to bulk balance....

??

 

[camebeloc]

Controller is just going bad is my guess at the moment. Nothing to do with the battery, 60v into a 72v controller should be fine. One last guess, is the controller getting any cooling air?

didn't know a controller could 'start' to go bad,,either ya blow it up or it works.....was my thinking, ,,,again folks, the 72 vcontroller WAS in the 48/20 SLA setup and dogman, its doesnt get a ton of airflow,,,,,but at 60v travelling quicker wouldn't it be 'getting more than it did on sla isn't it being as I am going much faster'!

 

[dnmun]

your controller may be (is) shutting off for high current. that was why i asked what was the current flow.

you use your wattmeter or cycle analyst to measure the current flow during the discharge of the battery.

from what you said that is what seems to be happening but we won't know until you can give us the current readings.

 

[camebeloc]

your controller may be (is) shutting off for high current. that was why i asked what was the current flow.

you use your wattmeter or cycle analyst to measure the current flow during the discharge of the battery.

from what you said that is what seems to be happening but we won't know until you can give us the current readings.

thnx dnmun!

ok. I will do. as I do have a turnigy watt meter, similar to a CA I believe, will charge her up and attach this

But dnmun, how will that show me an HVC level? it usually reads 67.2 at start when plugged into bike, and just goes down as I ride?

How WOULD I find if theres an HVC in the controller with a wattmeter?(sorry I'm no electricican!)

?

thnx gang for helping me with this!

 

[dogman dan]

Only way I'd know of would be to identify the make and model of the controller, then try to look up it's specifications. It might say it has a current limiter.

I still don't understand why the current limiter wasn't a problem with the sla's though. Wouldn't going faster have taken even more current?

Current limiter is going bad, and now tripping at less current is all I can come up with. I know squat about controllers, but I do know house circuit breakers wear out and start tripping at less amps.

 

[Ykick]

Only way I'd know of would be to identify the make and model of the controller, then try to look up it's specifications. It might say it has a current limiter.

I still don't understand why the current limiter wasn't a problem with the sla's though. Wouldn't going faster have taken even more current?

Current limiter is going bad, and now tripping at less current is all I can come up with. I know squat about controllers, but I do know house circuit breakers wear out and start tripping at less amps.

Not exactly. In my experience jumping from SLA to Lipo the controller may reach peak current at lower speed. It kinda depends on the controller but the fact remains when I ran saggy 48V SLA, my system would draw about 20-25A peak somewhere along the "acceleration" curve. When I moved to 60V RC Lipoly, Watt meter measures 30-35A with the same controller. Partly due to higher starting voltage/potential but also due to less sag compared to SLA.

Not sure how the Turnigy meter will respend to 67V though? Mine works up to 62V okay but I've read other folks not having as much luck with those above rated voltage?

I do know that power cutoff and restore by letting off the throttle is how over current protection works in ALL of the Infineon controllers I've ever used.

'sorry, I'm not extremely technical but I do use these things quite a bit and have managed to solve many issues with the help of good folks here on ES. Good luck with your issue. As has been suggested, measuring peak current is the place to start.

 

[dogman dan]

Yeah, I dig it that with little sag, you could spike the hell out of your amps leaving the line with lipo vs sla, or pull more in the meat of the acceleration.

But this is happening at cruise, when there should be a pretty straight line relationship between wattage and speed. It should have been more watts to go 60 kph before, than it's taking now to go 54 kph regardless of the current voltage under load.

I am assuming he can't feather the throttle, and tease it up to 60 kph.

But the controller will not be measuring watts, it will be measuring amps. And with more volts now, wouldn't it be less amps at 54kph-60kph? Makes no sense to me, unless something is sucking up current, or resisting it's flow.

I'm smelling a rat. Something is causing more current, What's getting hot now? Where is the extra resistance happening? The power is going someplace, and I bet it's heating something up.

Speaking of throttle, if he increased voltage, could something be going on there? Might be worth a look at his throttles red wire voltage. If it's 7v is that too much? So when he gives full throttle it shuts off in the controller? But then wouldn't it happen at any speed, any time full throttle was used?

You can get ebay controllers pretty cheap, I'd be heading in that direction at this point myself.

 

[dnmun]

i agree. would expect current to be related to speed. but it is something we need to know to eliminate it.

the HVC is something the BMS manages at the cell level. there is no pack level HVC. the HVC is cell level control over charging and has nothing to do with the discharge. if any cell reaches the HVC level of 3.9V then the BMS turns off the charging mosfet to stop that cell from overcharging and waits for the shunt transistor to drain the excess charge off of that cell before it turns the charging mosfet back on when the voltage drops to 3.8V or so.

if you can read your watt meter when the controller turns off then we can see if there is some way to increase the current level where your controller turns off.

the controller is not turning off for HVC. it is turning off because it thinks the current flowing through the controller is too high.

HVC and current control are two different things. the first is embedded in the BMS and the other in the controller.

 

[Ykick]

I'm baffled too. The original description is somewhat ambiguous - main thing missing is what's the throttle position when the motor cuts out at claimed speed? Is it hard WOT or mildly ramping up to top speed? Hell, maybe that controller has an overspeed function engaging?

I'm also not the guy to attempt a genuine technical explanation why current goes up with all of my controllers when I switched from 48V SLA to 60V RC Lipo. But, my meter tells me it did and my experience also tells me that throttle off resets over current condition. Not sure how any of this actually applies but it's all I can offer in an attempt to flush out the problem.

 

[dogman dan]

Current at the peak load moment at lower speed would definitely increase, and you'd see that for sure on a wattmeter that showed peak amps. I see that too, I see it if I go from 20c lipo to 30 c lipo that sags less.

No bms, so it's not a bms overcurrent cutoff. Sure acts like one. We'll just keep guessing blindly with the info we have now. Fun though.

Is the controller getting any cooling wind? Mabye its just running hotter now, and something inside stops working. Maybe it gets hot, and draws too much amps.

 

[leffex]

I'm baffled too. The original description is somewhat ambiguous - main thing missing is what's the throttle position when the motor cuts out at claimed speed? Is it hard WOT or mildly ramping it up...

For me, somthing similar to the thread owner started happening last week. I don't know exacly why.

I go full throttle, it turns of and after say 3 seconds starts again. The next day it happend again and with a half charged battery it was happening more often. Also going half throttle it does the same. Often it goes for 10 seconds and then it cuts off. Really no difference going up a hill, straight or down a road(current ). Turn of turn on battery it start again.

Changed controller from generic 15a to generic 3pin throttle to 30 amp with 4pin throttle. (I opened the 15a contorller and it had one 63v cap and two or three smaller 50v) My battery is fully charged at about 53v

Temperature i got minus 10 celsius a the moment. My bike stand inside at home and outside at work. Can it be small amounts of moisture in my motor shorting it?

How about moisture in throttles, it sure makes them go havoc.(like wide open not touching it....etc)

 

[www.recumbents.com]

He hasn't told us if he's just wanging the throttle from a stop or taking care to get up to speed. If he's just going wide open from a stop it may be causing a current or heat issue in the controller at the same time/speed each time he tries it. If he's just cruising along and then goes a little faster and it cuts out, yeah that would be strange.

-Warren.

 

[camebeloc]

He hasn't told us if he's just wanging the throttle from a stop or taking care to get up to speed. If he's just going wide open from a stop it may be causing a current or heat issue in the controller at the same time/speed each time he tries it. If he's just cruising along and then goes a little faster and it cuts out, yeah that would be strange.

-Warren.

Let me address some points mentioned...and a HUGE THANK YOU to all who have chimed in, some great info despite nothing I can see that is a cause yet.....

"He hasn't told us if he's just wanging the throttle from a stop or taking care to get up to speed. If he's just going wide open from a stop it may be causing a current or heat issue in the controller at the same time/speed each time he tries it. If he's just cruising along and then goes a little faster and it cuts out, yeah that would be strange."

Its the latter, I am gentle on throttle, and am cruising and adding only a SMALL amount as it reaches 54 k...it will cut out....I release and wait a second or two, byt then the speed has dropped slightly and if I come on the throttle again, it returns to power, but will not go over or past that 54 k......

Second point again folks, as I think some may be missing this: The SAME 72 v controller was in the 48/20 SLA setup and did not misbehave....only now on 60v(67.2 full charge) does this happen.......

and I am sorry gang, I don't have the know how to identify the controller or its specs....didn't think it would be that IT was the issue.....as it was in the 48/20 sla setup and was fine!

I was wondering if I tried either: going and testing the bike with less lipo voltage, and trying it closer to the 48 sla setup by shrinking my pack down a bteery each row.....

or conversely, going 72 v by adding a row, would either of these ideas bring any merit to this conversation? (the bike isnt out yet as in toronto it's still cool and roads not clear yet) but it should be out next week sometime, I will try anything!

finally, the ONLY thing else I can add, is when the guy did the upgrade he commented on how T H I N the motor(or phase or both?) wires were,,,could this be causing an issue wit the higher voltage? and should that make me AVOID going to 72 v trial? as I dont wanna blow it up,,,54 k better than zero k..lol!

The plot continues......thanks so much gang for all trying to hellp, what a great forum ES is!

 

[Ykick]

He hasn't told us if he's just wanging the throttle from a stop or taking care to get up to speed. If he's just going wide open from a stop it may be causing a current or heat issue in the controller at the same time/speed each time he tries it. If he's just cruising along and then goes a little faster and it cuts out, yeah that would be strange.

-Warren.

Let me address some points mentioned...and a HUGE THANK YOU to all who have chimed in, some great info despite nothing I can see that is a cause yet.....

"He hasn't told us if he's just wanging the throttle from a stop or taking care to get up to speed. If he's just going wide open from a stop it may be causing a current or heat issue in the controller at the same time/speed each time he tries it. If he's just cruising along and then goes a little faster and it cuts out, yeah that would be strange."

Its the latter, I am gentle on throttle, and am cruising and adding only a SMALL amount as it reaches 54 k...it will cut out....I release and wait a second or two, byt then the speed has dropped slightly and if I come on the throttle again, it returns to power, but will not go over or past that 54 k......

Second point again folks, as I think some may be missing this: The SAME 72 v controller was in the 48/20 SLA setup and did not misbehave....only now on 60v(67.2 full charge) does this happen.......

and I am sorry gang, I don't have the know how to identify the controller or its specs....didn't think it would be that IT was the issue.....as it was in the 48/20 sla setup and was fine!

I was wondering if I tried either: going and testing the bike with less lipo voltage, and trying it closer to the 48 sla setup by shrinking my pack down a bteery each row.....

or conversely, going 72 v by adding a row, would either of these ideas bring any merit to this conversation? (the bike isnt out yet as in toronto it's still cool and roads not clear yet) but it should be out next week sometime, I will try anything!

finally, the ONLY thing else I can add, is when the guy did the upgrade he commented on how T H I N the motor(or phase or both?) wires were,,,could this be causing an issue wit the higher voltage? and should that make me AVOID going to 72 v trial? as I dont wanna blow it up,,,54 k better than zero k..lol!

The plot continues......thanks so much gang for all trying to hellp, what a great forum ES is!

Okay, that's helpful - all that I can suspect is it's speed related. Perhaps that controller has a speed limit?

 

[camebeloc]

"Okay, that's helpful - all that I can suspect is it's speed related. Perhaps that controller has a speed limit?"

Thanks ykick again, but no I don't think this is true, reason I say this is because the guy that had this controller before me, was running it in a 72 v lipo gio maxed at 84 volts on full charge....and he didn't have any issue's.....

the plot thickens...

ok guys, the bike comes out to ride next week, anything I should try?

does my idea of trying maybe less lipo say 48 v, or more....conversely 72 v lipo, have any merit to the 'cutoff or power issue'?

?

 

[Ykick]

"Okay, that's helpful - all that I can suspect is it's speed related. Perhaps that controller has a speed limit?"

Thanks ykick again, but no I don't think this is true, reason I say this is because the guy that had this controller before me, was running it in a 72 v lipo gio maxed at 84 volts on full charge....and he didn't have any issue's.....

the plot thickens...

ok guys, the bike comes out to ride next week, anything I should try?

does my idea of trying maybe less lipo say 48 v, or more....conversely 72 v lipo, have any merit to the 'cutoff or power issue'?

?

I've never seen a controller speed limit - that was merely "suspicion" or a possiblity...

Drop down to 12S (50V Hot) and see what happens. Do you have a power meter yet? Very high priority IMO if you want to know what the system is doing in regard to electrical performance.

Good luck, 'hope you find the solution soon!

 

[hydro-one]

could the controller be advancing the timing at some speed in order to weaken the field so a lower voltage setup can reach higher speeds(stock sla). When confronted with a higher voltage, it draws too much current at that point and trips the hard limit.......I have a lyen 12 fet that does this with the hs35. seems to have two "speeds", like a turbo almost. but it really sucks the amps when it changes to high .

I think the op should try some lower voltage lipo to see what happens.

 

[camebeloc]

"Okay, that's helpful - all that I can suspect is it's speed related. Perhaps that controller has a speed limit?"

Thanks ykick again, but no I don't think this is true, reason I say this is because the guy that had this controller before me, was running it in a 72 v lipo gio maxed at 84 volts on full charge....and he didn't have any issue's.....

the plot thickens...

ok guys, the bike comes out to ride next week, anything I should try?

does my idea of trying maybe less lipo say 48 v, or more....conversely 72 v lipo, have any merit to the 'cutoff or power issue'?

?

I've never seen a controller speed limit - that was merely "suspicion" or a possiblity...

Drop down to 12S (50V Hot) and see what happens. Do you have a power meter yet? Very high priority IMO if you want to know what the system is doing in regard to electrical performance.

Good luck, 'hope you find the solution soon!

Thanks again ykick for keeping on, and ok, I will do just that...and yes, I have the Turnigy WATTMETER, similar to a CA I believe, that should work

When she comes out, I will try her on that 50v and report any findings and measurements next week if it ever warms up and stays warm here in Toronto(late spring)...thnx

cheers