hot electrics troubleshooting

[Lexicon]

Hello All,

I am new here i found the place after a google search and wondered if someone could help with my predicament.~
I have a fat tyre ebike, it hsa 2 500w motors, wired to 2 seperate 22a -/+2a 48v presumably one for the back and one for the front.

anyway last year i opened the bottom box up to take a look and found that the 3 phase wires had melted through the insulation on the crimp connectors that were used when it was built.

anyway i replaced these with 32 amp connectors that had a high tempurature resistance on the plastic and this sorted me out.

however fast forward a year later and i decided to do a checkup on it. i found that now all the hotglue they put into all the connectors etc had melted. stuck everything together. the connectors are fine didnt melt them but im thinking that the heat these wires are giving off shouldnt be happening at all and wondering if anyone had an idea what it could be.

anyway i figured it could be the connectors so i took them off and directly soldered the wires together instead. i got back from work today with the plan ill check it to see how hot its getting. and i found it was hitting 80 degrees c. see thermal image below.

now im thinking that the issue could be

1. Needs better wriing, maybe a better guage.
2. Controller is causing it. (not suitable for the load on the wires)

If it is the controller i would probably end up rewiring the entire thing as i would want to change to use a single controller for both

 

[DieselTech]

Hello All,

I am new here i found the place after a google search and wondered if someone could help with my predicament.~
I have a fat tyre ebike, it hsa 2 500w motors, wired to 2 seperate 22a -/+2a 48v presumably one for the back and one for the front.

anyway last year i opened the bottom box up to take a look and found that the 3 phase wires had melted through the insulation on the crimp connectors that were used when it was built.

anyway i replaced these with 32 amp connectors that had a high tempurature resistance on the plastic and this sorted me out.

however fast forward a year later and i decided to do a checkup on it. i found that now all the hotglue they put into all the connectors etc had melted. stuck everything together. the connectors are fine didnt melt them but im thinking that the heat these wires are giving off shouldnt be happening at all and wondering if anyone had an idea what it could be.

anyway i figured it could be the connectors so i took them off and directly soldered the wires together instead. i got back from work today with the plan ill check it to see how hot its getting. and i found it was hitting 80 degrees c. see thermal image below.

now im thinking that the issue could be

1. Needs better wriing, maybe a better guage.
2. Controller is causing it. (not suitable for the load on the wires)

If it is the controller i would probably end up rewiring the entire thing as i would want to change to use a single controller for both

View attachment 13641

Does your other controller show a heat signature like the one you got pictured?

Are you running a single battery or dual?

Is 1 controller more confined to space than the other controller?

Thanks.

 

[Lexicon]

Does your other controller show a heat signature like the one you got pictured?

Are you running a single battery or dual?

Is 1 controller more confined to space than the other controller?

Thanks.

Single battery. the 1 controller is under the bike, they are both confined to around the same space.
i think it probably does but not as bad. i think its how they tapped into the power.

it looks as though its this cable thats heating up which is the power from the battery. cable above is the bottom. it leads into the top of the bottom image which diverts off to both controllers. i think this could be the fault.

That said on the way back from work today i lost all power whilst going up a hill, probably from the extra power draw the motors are taking by going up hill. the displays battery meter went to 1 bar and displayed an error think it said e06 which would suggest undervoltage. but i guess this could happen if suddenly the resistance somewhere skyrocketed. if the battery went the display wouldnt be on and pretty sure it was around half full

Please excuse the hot glue covered wires lol it made a right mess

 

[DieselTech]

Single battery. the 1 controller is under the bike, they are both confined to around the same space.
i think it probably does but not as bad. i think its how they tapped into the power.
View attachment 13659

it looks as though its this cable thats heating up which is the power from the battery. cable above is the bottom. it leads into the top of the bottom image which diverts off to both controllers. i think this could be the fault.
View attachment 13660

That said on the way back from work today i lost all power whilst going up a hill, probably from the extra power draw the motors are taking by going up hill. the displays battery meter went to 1 bar and displayed an error think it said e06 which would suggest undervoltage. but i guess this could happen if suddenly the resistance somewhere skyrocketed. if the battery went the display wouldnt be on and pretty sure it was around half full

Please excuse the hot glue covered wires lol it made a right mess

Yeah I was going to mention the battery connection/splice for the controllers.

With that thermal imager you should be able to see the hot spot in that connection for the power cables to the controllers.

I think you are on the right track.

 

[Lexicon]

Yeah I was going to mention the battery connection/splice for the controllers.

With that thermal imager you should be able to see the hot spot in that connection for the power cables to the controllers.

I think you are on the right track.

i stripped away the cable to find this guessing its an inline fuse for the controller. only thing it could be.

can see the postives connection wasnt all that good. was probably what caused it to hit up

 

[DieselTech]

i stripped away the cable to find this guessing its an inline fuse for the controller. only thing it could be.

can see the postives connection wasnt all that good. was probably what caused it to hit up
View attachment 13663

Looks like it got hot enough to melt the solder on that 1 connection. I would maybe switch over to the XT90 connector, I think they will handle more amperage than the style pictured. But I may be wrong.