230vac EV Home Charger blowing fuses

[Tom French]

This just started, after I had the front bumper take off at the dealers to paint it.
The output 20A fuse blows over night charging. The fuse in the house panel never trips.
When I tried the 120vac charger, the cord gets pretty warm, is that normal for the 120vac.?

 

[breeves002]

What 20a fuse blows?

Are you using a 30a EVSE? If so the fuse for each hot wire should be 40a. The house panel is a 40a breaker?

If you have a clamp meter you can check the amperage by clamping around one of the hot wires. I don't know what you can access in the EVSE or what you have. You can also check the line voltage and charging amperage by using FORScan with the SOBDM which monitors the charger.

The 120v cord can get warm, so can the plug.

 

[Tom French]

breeves02

I was blinded by stupidity, in a hurry to get to work, all I noticed was no lights on the EVSE.
When I soldered the fuse back in, I put the cover on with shipping tape, just in case I had to open it again.

When I got home I noticed the cover was on the ground, so the LEDs would be off, DUH !
Put back together with the screws this time.

I plugged back in, and it was still working. So it is not dead. I could get a clamp amp meter at work to borrow if needed.
So glad it is not damaged.

 

[Tom French]

Mine has the same problem, had it for 4 years.
replaced with a 30A pig tail fuse a year ago.

Now last night it blew the fuse again.

Not sure why, I had a front end crash about 4 months ago, and had most replaced on the EV.

Did you find anything out.?

 

[Tom French]

This is the pig tail fuse 30amp. that I used. The fuse it is replacing is a 20amp.

Again the other fuse was blown this time.

Next time it should trip the breaker.

 

[Tom French]

When I replaced the fuses, and them mounted the PCB back in the EV charger, I performed a pull test on each of the wires for HV.
Found the RED wire on the bottom strip to exit charge was easily pulled out. so re-secured it. This can induce a higher amp to charge, and could be the reason it blew the fuse.

 

[JTCalif]

Doubt that pulling on any wire could cause more current flow; might cause higher resistance (so Less current), OR conceivably move a loose strand to short to an adjacent conductor (?).
What is rating of the EVSE? Original fuse should be a bit above that rating.
Ford's 120 V "charger" normally runs quite warm, I read; I never use it.

Have you been using that EVSE for a long time? If so, question why its fuse wants changing. Do not risk a fire hazard with deteriorating device: makes more sense to get a newer one (and match your wiring and breakers).