MauryH
New Reader
4/7/23 4:54 p.m.
Is fire the only concern in a EV crash? Someone mentioned loose wires, but seems to me the high voltage threat to first responders is as big an issue as fire. Getting a trapped driver out of an EV, on fire or not, the possibility of electrocution could be a major threat to the rescue crew it seems to me.
In reply to MauryH :
Not really. The only potential electric shock threat is if you have both hands inside an HV system. This is not something a first responder is going to be doing.
People think about down power lines when they think of EVs but they are different in that an EV is self contained. A power line has high voltage potential between the wire and ground. You can get shocked from touching a power line and ground because you are completing a circuit. This is not the case when the ground is not part of the circuit like in an EV.
It is similar to an ICE where you technically have 50,000 volts flowing through the ignition coil - plug wire - distributor - plug wire - spark plug - ground interface, but you don't get shocked by touching a running car. You have to go and get between a plug wire and chassis ground to do that.
And no EV on the planet uses chassis ground as part of its HV system, on purpose.
tl;dr: if there were a situation in an EV crash where a responder might get shocked, the car is already on fire
SV reX
MegaDork
4/7/23 8:25 p.m.
In reply to Pete. (l33t FS) :
That's good info, but I wouldn't assume first responders are gonna just stand back.
If the twisted car is on fire and someone is screaming inside, first responders are gonna respond. That's what they do. And throwing water or foam on it (like they do gas fires) is the wrong response.
The training matters, and track personnel need to be trained. If a track has not adequately trained its personnel (and doesn't know HOW to train them yet), they need to put a hold on EV racing until they have a comfort level with both the technology and their level of training.
It's temporary, but absolutely necessary.
In regards to shock hazard.
The contactors would have to get stuck, they usually failsafe and are right at the battery.
In reply to SV reX :
There is, potentially (har har) a possibility for the contactor to NOT open. One of my trainers was relating a story about a certain vehicle (not a Prius, not a Tesla, is all I remember) where there was measured voltage between an HV wire and ground, on a vehicle that saw no reason to open the contactor. Which in theory shouldn't happen of course.
But still, no HV between, say, a door and the doorsill. Or the chassis and the steering wheel. You'd have to open up the battery case (which are designed like fuel cell cans, not handheld flashlights) and touch one of the cabling studs and chassis ground to get a shock. The vehicle in question had been driven in to the repair facility and they had been working on it and there was no measured HV anywhere on the chassis except between the orange-sheathed cables and the chassis ground.
Your points about throwing possibly conductive fluids around are valid, but if there were a worst case scenario situation where wiring was breached, a first responder or the driver is not going to become one of the resistors in that particular circuit. If the cables contacted the chassis, and the conductors didn't open, there would be a glorious fire but still no shock threat.
SV reX
MegaDork
4/7/23 9:09 p.m.
I never said there was shock threat. I said a wrecked EV is dangerous and requires specialized training to approach, which some tracks are not prepared for.
Race cars with high voltage batteries (such as F1) often have lights on them to tell the marshals if the car is "safe" or not. On occasion those lights are lit red to indicate "unsafe" after an incident, and we sometimes see drivers jumping off the car to avoid making a path to ground.
There's lots of money in F1 and they were an early adopter of electric power in pro race cars (in the form of KERS), so perhaps they're overly conservative in this regard, but it suggests that someone thinks the risk of a shock is non-trivial.
codrus (Forum Supporter) said:
Race cars with high voltage batteries (such as F1) often have lights on them to tell the marshals if the car is "safe" or not. On occasion those lights are lit red to indicate "unsafe" after an incident, and we sometimes see drivers jumping off the car to avoid making a path to ground.
That literally just happened at the last race, Hulkenberg was told over the radio to stop the car immediately after the checkered flag and "you need to do an ERS jumpout because the car is not safe".
codrus (Forum Supporter) said:
Race cars with high voltage batteries (such as F1) often have lights on them to tell the marshals if the car is "safe" or not. On occasion those lights are lit red to indicate "unsafe" after an incident, and we sometimes see drivers jumping off the car to avoid making a path to ground.
Why would they need to do that?
Pete. (l33t FS) said:
codrus (Forum Supporter) said:
Race cars with high voltage batteries (such as F1) often have lights on them to tell the marshals if the car is "safe" or not. On occasion those lights are lit red to indicate "unsafe" after an incident, and we sometimes see drivers jumping off the car to avoid making a path to ground.
Why would they need to do that?
Dunno, but it's enough of a concern that they have a procedure for handling it.
In reply to codrus (Forum Supporter) :
If they weren't wearing seatbelts, they'd be thrown clear of the wreckage!
I honestly can't fathom..... There is no "path to ground" for an EV unless it happens to have a down power line draped across it.
Maybe they should pave the courses with concrete instead of asphalt. After all, everyone knows a battery drains itself if it is set down on concrete
https://www.repairerdrivennews.com/2021/01/18/ntsb-report-highlights-safety-risks-precautions-for-electric-vehicle-towing-storage/
The NTSB and SAE talk a lot about Stranded Energy and Thermal Runaway. The Stranded Energy is a big concern for first responders.
Unfortunately, it looks like this decision has cost us the EV that has competed in the 25 Hours of Thunderhill. The team is based at Summit Point and were always exciting to watch.
This could possibly be one of the saddest days of my entire career.
With our home track, Summit Point, banning EVs after 10 years of safe, and successful events, and the SCCA creating an EV rules committee with a self appointed chairman making rules to exclude the only car that has regularly run, and been twice approved by national.
Quitting is sometimes sad but sometimes it leads to better things.
Somebody needs to pick up where I left off and I can make it easy.
I am proud of what the team has done, and built, and the results speak for themselves. They just don’t have a very loud voice.
This is apparently the SCCA rule committee referenced: https://www.scca.com/articles/2016833-electrified-vehicle-advisory-committee-charges-forward
This is the team that was doing battery swaps in pit stops, and here's one that only took 85 seconds with a driver change: https://fb.watch/jPWtF3eOMO/?mibextid=kdkkhi
Toyman!
MegaDork
4/10/23 12:25 p.m.
In reply to Keith Tanner :
That's pretty impressive.
I'm curious why they banned battery swaps.
SV reX
MegaDork
4/10/23 12:46 p.m.
In reply to Toyman! :
I'd guess lack of thorough understanding (like most of this).
SV reX
MegaDork
4/10/23 12:51 p.m.
In reply to Keith Tanner :
I agree that sidelining that team (for a while) is unfortunate. We'd all like to see EVs move forward (and it sounds like the SCCA wants it too)
Note however, that being "safe" and being "incident free" are not the same thing.
The entire history of racing is littered with teams that got sidelined for something that was later determined to be "unsafe".
It really is temporary.
In reply to SV reX :
I'll bet if you reached out to that team you'd have an interesting conversation. "Safe" was a priority, including their choice of a safer but lower performance battery chemistry.
Will all the floods in this country , what happens to EVs ( yes I know they are not all the same) when they are totally underwater ?
Do they have some kind of circuit breaker when there is a direct short ?
Without reading too much into the discourse, seems like Summit Point is going to research the best way to move forward to avoid insurance and OSHA liabilities at the time and that is all there is to it.
Nothing wrong with taking time to come up with a proper plan and resources to address any potential issues that may arise with allowing hybrids and EVs in a performance environment.
SV reX
MegaDork
4/10/23 2:47 p.m.
Keith Tanner said:
In reply to SV reX :
I'll bet if you reached out to that team you'd have an interesting conversation. "Safe" was a priority, including their choice of a safer but lower performance battery chemistry.
I have no doubt they did a fantastic job. That has NOTHING to do with the business decision. That's why I put the word "safe" in quotes.
I have a 45 year track record of having never had a single injury or incident at any construction job site that sent anyone to the hospital or caused any lost time at work. But when OSHA inspected me earlier this year, they made sure to fine us over $25,000 in fines (for extension cords laying on the floor).
"Safe" isn't determined by track record, or by lack of incidents. "Safe" is determined by insurance companies and by legislators.
It's not a racing decision. It's a business decision.
However, I did watch the video. I am very impressed with their 85 second pit, but I saw a bunch of people go over the wall, and none of them are wearing safety glasses, helmets, or Hi-Vis. And a couple of them stood directly in front of the car as it came to a stop. There are always ways to improve safety.
We'd all like to see the EV racing go forward. But this is a business decision right now, for a legitimate perceived risk.
It will change.
You have made your point clearly and repeatedly. I don't think anyone is disagreeing with you on the "emergency crews must be prepared" concept. I disagree that "safe" is determined by legislators and insurers as opposed to actual track record, because those paper pushers have to work from SOME data from someone.
But there are consequences, I was just pointing one out. One of the innovators in this kind of racing is shutting down, which means less data for the paper pushers. This is a team that prioritized building a car that minimized the chances of something happening, so they are just the sort we can least afford to lose.
The pit stop was made under NASA's Thunderhill's 25 hour rule set. The lack of helmets, glasses or high-viz jackets or personnel placement during a driver change and work on the car has nothing to do with the fact that it's an EV. I've worked several positions on those pit stops in that race, that's normal.
SV reX
MegaDork
4/10/23 3:55 p.m.
In reply to Keith Tanner :
I know how passionate you are about EVs, and about advocating for them in every way possible. You have made me a believer.
But you are pushing back really hard on this. As far as I am concerned, Summit (or any other track) can make whatever rules and choices they see fit. It's a private business. Their choice to limit EVs for now is purely a liability decision, which is no different than Flyin Miata's choice to stop building cars with engine swaps.
There is no one I respect more than you on this board, especially when it comes to EVs (and of course Miata's!). But your pushback to everyone in this thread regarding your opinion on safety isn't one of your best moments.
You have also made your point clearly and repeatedly. You disagree with the business decision Summit (and others) are making. Consider yourself heard.
Feel free to petition the SCCA for changes. I will look forward to them. But arguing about it here doesn't accomplish much. I'm not on the SCCA rule committee.
I'm not pushing back hard :) Heck, I haven't even posted in this thread for a week.
I completely agree with the decision to stop running EVs until the emergency procedures/training are in place, I've said that all along. The high end pro race series are the places to look for that, there's a lot of data coming out of F1 and the WEC with regards to EVs and hybrids. Hopefully the SCCA is looking that way.
Unfortunately, it has cost us what is probably the best grassroots level effort to make an endurance battery EV, one that was competing at a national level. That's not an opinion or pushing back, it's a fact.
And FM's decision to stop building engine swaps was not purely a liability decision, but like EVs there is a whole lot of bad info out there from outlets that are more exciteable than accurate :)
I am curious, now, what the safety protocols, if any, are in place for WRC, given that they are throwing hybrid vehicles sideways at trees 2m off the ground, necessarily far from civilization.
californiamilleghia said:
Will all the floods in this country , what happens to EVs ( yes I know they are not all the same) when they are totally underwater ?
Do they have some kind of circuit breaker when there is a direct short ?
I can tell you that after Hurricane Ian, there were plenty of EV fires from cars that had been in enough salt water to reach the batteries.