melted connector on ODK U500 v3

[Jep]

A little while ago my motor on ODK U500 stopped working and the problem appeared to be with the connector that comes out of the front hub motor: it was stuck.

I managed to pry it apart and it had actually melted internally, likely due to high electrical current since it's never really hot here in San Francisco. See pictures below. Has anyone had similar issues? I would assume a fuse would blow in case of high current, but apparently that didn't happen. Thoughts? The bike is 2 years old and has the 32Ah battery.

Thanks,
Jep

 

[Luis Mtz]

Hi Jep, we reached out via your ticket confirming the parts in stock. In this case seems like moisture or debris got in the connection.

We suggest cleaning the connections using a can of compressed air for preventive maintenance.

 

[Jep]

@Luis Mtz thanks for confirming. I somehow have not received any emails from Juiced support in the past week. Can you please resend and/or use my Gmail address 'jepcastelein@*****.com' (fill in 'gmail'). Thanks!

 

[Reid]

It happened that the connection was dirty or otherwise imperfect. All the current was going through a small, concentrated spot. This caused local heating sufficient to melt the plastic.

It is important to always blow out our connectors of this type with compressed air, and if we use a light bodied dielectric grease to help protect against corrosion or water ingress, don't use so much as to create a hydraulic block against the pins fully seating.

Compressed air is a great thing to use to ensure connector sockets and pins are sufficiently clean to make full contact. The pins are long for a practical reason: to ensure enough current carrying contact area.

A fuse will not blow in the case of a dirty connector causing high local current because spotty contact does not cause any increased current; Spotty contact only causes all the current to pass through a more or less small point of contact interface. Resistance ensues and power is converted to heat. Spot welders work on this principle.

 

[Jep]

Thanks for the detailed explanation @Reid , that's what must have happened. I will regularly check and clean the connectors going forward.