Stop Safely Now (HVBJB): Mach-E Owners Biggest Fear - Facts and Info Thread

[Fixbear]

I may be off base here, but it seems that Most of the reported failures have been with extreme temps. Both Hot and cold. That means the LVB will be under considerable load for temperature regulation of both the cabin and HVB. So it's voltage will be at a lower state. A lower control voltage on a contactor will do several things, Chatter, sluggish or delayed pull in, Failure to have enough Gauss to even close. I'm certain that Fords engineers have looked at that. But they can't say anything. It seems to be the common thread.

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[Addos]

I may be off base here, but it seems that Most of the reported failures have been with extreme temps. Both Hot and cold. That means the LVB will be under considerable load for temperature regulation of both the cabin and HVB. So it's voltage will be at a lower state. A lower control voltage on a contactor will do several things, Chatter, sluggish or delayed pull in, Failure to have enough Gauss to even close. I'm certain that Fords engineers have looked at that. But they can't say anything. It seems to be the common thread.

With the weather being like it has been and looks like it will continue to be, this type of problem looks more and more likely, if indeed this is what is triggering the issue to happen. So then the question is, will the proposed software update actually resolve the issue, or is it just trying to extend the life of the faulty part long enough to not have to cover it under warranty when it eventually fails?

 

[FordMachEGo]

What causes a Contactor to fail:

Contactor failure symptoms: Reasons for contactor failure (electricalterminology.com)

• Overcurrent in the main contacts
  • High current carrying loads create heat at the main contacts of the contactor, this causes welding in the closed position
  • Pole wear during the contactors lifetime
• Overvoltage and undervoltage in the coil
  • Operational limit of the contractor is between 85 and 110% of the rated coil
  • Voltage variation of +- 5% of the above limits will increase the contact bounce that leads to increase contact wear.
    • Higher voltages will increase the speed of the electromagnet at closing
    • Lower voltages will decrease the speed at closing
    • Both of these lead to higher level of contact bounce at closing
  • High voltage and increased speed at closing also contributes to some increased sound
  • Control voltage of less that 85% during pick up may not be enough to safely close the contactor and cause the coil to melt due to overheating
    • This is because the coil is designed to withstand the inrush current for a limited time only
    • One common reason: coil supply is taken from main supply where a high current is causing the voltage to drop
      • Too high continuous control voltage could also cause the coil to melt.
• Wrong product selection
  • Contactors should be selected according to the type of load
    • Conditions under which making or breaking takes place: motor stalled, starting or running, reversing, plugging.
• Voltage drop during start-up of the motor
  • Voltage drop to less that 85% of normal voltage for 5 to 10 ms can be enough for the contactors to start opening, resulting in increased contact wear and/or welding of main contracts
• Current peaks used by heavy-duty starting
  • If the application requires a high level of torque during start-up, it is important that the contactors making capacity and short-time withstand currents are capable of handling the starting current and current peak
• Restarting with motor idling
  • Attempting to restart the motor before it has come to a full stop will cause a peak that theoretically can reach twice the current comparted to starting the motor from a standstill, this ca result in welding contacts
• Change over time between star and delta
  • Setting the change over time between star and delta too short will not allow the motor to reach 80-90% of its nominal speed causing star contactor to break a high current that expected
  • Open and close timing between star and delta
• Product coordination
  • Lack of product coordination with fuse or breaker missing or wrongly sized can cause excessing contact wear or lead to welded contacts.
• High temperature
  • High temperature causes contract welding and coil melting.
  • The standards define temp raising regarding the ambient temp.
  • If the contactor is overheating, you will have to SUM the ambient temp and the temperature rise allowed.
    • Connections properly torqued
    • Ventilation of electrical panel
    • Cable size is what is recommended
    • Correct coil is selected for the application
• Wrong cable selection
  • Incorrect cable selection to current levels creates cable overheating, consequence is contactor overheated.
• Vibration
  • Selection of High Vibration and Shock parameters of the contactors
• Environmental Factors
  • Pollution of the magnet pole surface will create a slight hum coming from the contactor in the closed position
  • Pole surfaces are deformed
  • Condensation, keep pole surfaces of magnet free from corrosion
  • Should be located in an enclosure, protection from dust and water
• Connection and mounting mistakes
  • Torque values
    • Loose connection on the terminal creates overheating
    • Tight connection could damage terminal screw
• High altitudes
  • Decreased in atmospheric pressure, the spacing required to prevent flashover increases substantially

Obviously we are doomed.

 

[P. T. Magoo]

I may be off base here, but it seems that Most of the reported failures have been with extreme temps. Both Hot and cold. That means the LVB will be under considerable load for temperature regulation of both the cabin and HVB. So it's voltage will be at a lower state. A lower control voltage on a contactor will do several things, Chatter, sluggish or delayed pull in, Failure to have enough Gauss to even close. I'm certain that Fords engineers have looked at that. But they can't say anything. It seems to be the common thread.

With the weather being like it has been and looks like it will continue to be, this type of problem looks more and more likely, if indeed this is what is triggering the issue to happen. So then the question is, will the proposed software update actually resolve the issue, or is it just trying to extend the life of the faulty part long enough to not have to cover it under warranty when it eventually fails?

These posts make me wonder whether:
a) the software patch might include changes to the charging strategy for the LVB, and;
b) the extra 50K miles in my extended warranty might just put the joke back on Ford.
Either way, I'd likely upgrade to the new HVBJB if the option were offered. I like upgrading my cars.

 

[jonkMACHE]

Does anyone have pics of the old/new HVBJB? Specifically a close up of the contractors would be nice. Would love to see what the difference is.

 

[rcechinel]

Does anyone have pics of the old/new HVBJB? Specifically a close up of the contractors would be nice. Would love to see what the difference is.

I guess everybody would... I doubt we will, for a while.

 

[sotek2345]

These posts make me wonder whether:
a) the software patch might include changes to the charging strategy for the LVB, and;
b) the extra 50K miles in my extended warranty might just put the joke back on Ford.
Either way, I'd likely upgrade to the new HVBJB if the option were offered. I like upgrading my cars.

Just FYI - I would check that extended warranty. I would guess that the HVBJB is not included as it is part of the EV drivetrain which they typically don't cover (since all of those components have the 8 year / 100k warranty).

 

[P. T. Magoo]

Just FYI - I would check that extended warranty. I would guess that the HVBJB is not included as it is part of the EV drivetrain which they typically don't cover (since all of those components have the 8 year / 100k warranty).

Hmmm.... I will do that. I signed up due to the immediate rental car whatever the problem, and the extra 50K miles, as I'll surely hit 150k before I hit 8 years. But if it doesn't cover the stuff that makes this an EV (the stuff I won't be able to fix with tools and skills I already have), then what would be the point really?

Much obliged and I will have a look at that.

 

[Addos]

Ford needs to really step up it's game and test the shit out of this part to give more specifics on exactly what set of conditions is causing it to fail. These vague responses, and the attempt to sweep it under the rug with a software update aren't exactly inspiring confidence.

 

[Joules]

Does anyone have pics of the old/new HVBJB? Specifically a close up of the contractors would be nice. Would love to see what the difference is.

I think you can see the part in question at thread below. https://www.macheforum.com/site/threads/my-stop-safely-now-saga.17610/

 

[scoopman]

I think you can see the part in question at thread below. https://www.macheforum.com/site/threads/my-stop-safely-now-saga.17610/

We have photos of the old part, not of the new part to see what is different. At least I don’t remember any photos yet from someone who has gotten the new one. Perhaps @VegStang can try and get us some?

 

[rcechinel]

We have photos of the old part, not of the new part to see what is different. At least I don’t remember any photos yet from someone who has gotten the new one. Perhaps @VegStang can try and get us some?

Sorry about the newbie question, is this the HVBJB part?

 

[DevSecOps]

Sorry about the newbie question, is this the HVBJB part?

Negative

 

[macchiaz-o]

Sorry about the newbie question, is this the HVBJB part?

The HVBJB is the beige/mustard colored assembly shown at the bottom of this photo, which is at the front end of the battery pack.

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