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High voltage equipment in battery-powerd cars

High voltage equipment in battery-powerd cars

High voltage equipment in battery-powerd cars

(OP)
Hi,

1/2 year ago, we discussed in Germany the elektical problems of electrical cars (Lithium - Ion - accu).

Specially BMW i3 and Tesla.

In the result, we can say there ist no chance for the fire-fighters to help passangers in destroyed cars after an accident.
The personal protective equipment of the fire-fighters is missing.
The safty of the passengers is not garantied.

5 weeks ago, the 9-page report ins gone to the German Government, to the german car observer office (KBA - Kraftfahrtbundesamt),
and to Tesla Germany.


Sincerely


.pdf Text: E-car Report in german


Write to Tesla:


Sehr geehrte Damen und Herren,


anbei erhalten ein 9-Seitiges Dossier über die Sicherheit, besser gesagt die Unsicherheit, von E-Fahrzeugen mit Batterie.

Das Bundesverkehrsministerium hat das Gutachten vor zwei Wochen erhalten.

In der Zusammenfassung ist festzuhalten, daß ein sorgenfreier Betrieb von E-Fahrzeugen mit Lithiumbatterie in Deutschland nicht möglich ist.
Konsequenterweise müssten alle diesbezüglichen Betriebserlaubnisse vom KBA zurückgenommen werden.

Zusammenfassung

- Ersthelfer können an verunfallten E-Autos nicht agieren, ohne sich selbst zu gefährden.

- Eine ADR – Kennzeichnung von Batteriefahrzeugen wäre wünschenswert.

- Die Deutschen Feuerwehren besitzen derzeit keine zugelassene PSA, um an verunfallten E-Fahrzeugen Technische Hilfe leisten zu können.

- Die Deutschen Feuerwehren haben keine Beladung auf den Einsatzfahrzeugen, um brennende Lithiumbatterien zu löschen.

Es gibt noch eine Reihe weiterer Probleme:

Durch den Umstand, daß Batteriegestützte E-Fahrzeuge rollende Elektroanlagen sind,
benötigt die Feuerwehr zwingend Elektrofachkräfte im Einsatz (die bei Freiwilligen Feuerwehren bisher kaum vorhanden sind).
Zudem muß vom Chef der Feuerwehr (in Gemeinden i.d.R. der Ordnungsamtsleiter) der im Einsatzfall agierende Gruppenführer
schriftlich zur VEFK (Verantwortlichen Elektrofachkraft) ernannt werden.
Unterlässt er es, liegt ein Organisationsverschulden vor.
Das dürfte bei 99 % der Deutschen Gemeindeverwaltungen unbekannt sein.
Aufgund der Menge an Lithium-Batterien ist jedes Batteriegestützte E-Fahrzeug aus Gründen der Physik ein Gefahrguttransport.


MfG


In English (google translator):

Dear Sir or Madam,


Enclosed are a 9-page dossier on the safety, or rather the uncertainty, of -vehicles with battery.

The Federal Ministry of Transport received the report two weeks ago.

It should be noted in the summary that carefree operation of e-vehicles with lithium battery in Germany is not possible.
Consequently, all relevant operating permits would have to be withdrawn by the KBA.

Summary

- First responders can not act on accidental electric cars without endangering themselves.

- ADR labeling of battery vehicles would be desirable.

- The German fire brigades do not currently have approved PPE to provide technical assistance to accident-damaged electric vehicles.

- The German fire brigades have no load on the emergency vehicles to extinguish burning lithium batteries.

There are a number of other problems:

Due to the fact that battery-powered e-vehicles are rolling high power electrical systems,
the fire brigade necessarily requires electricians in action (which are so far hardly available in volunteer fire departments).
In addition, the chief of the fire brigade (in municipalities i.d.R., the 'Ordnungsamtsleiter' (= Chief of stuff))
must act in the case of a group leader be appointed in writing to the VEFK (responsible electrician).
If he fails, there is an organizational fault.
That should be unknown in 99% of the German municipalities.
Due to the amount of lithium batteries, every battery-powered e-vehicle is a dangerous goods transport for physics reasons.


Kind regards

-----------------------------------------

Now the questions:

What situation do you have in America ?
Whitch protective equipment (DC < 1'000 Volt) of the fire-fighters do you have ?

Max

RE: High voltage equipment in battery-powerd cars

The manufacturers have already done what they can to pre-empt such concerns. There is plenty of guidance available.

E.g. Tesla https://www.tesla.com/firstresponders
E.g. Mercedes http://www.bbc.com/news/technology-22682186 (bar codes)

The pack should have an isolation relay that would open circuit the pack after a crash. It's possible that such protection could fail. So caution is required.

Some vehicles have a "Cut Here" point to mechanically cut a wire to isolate the pack.

In the worst case, perhaps a battery pack would suffer internal short circuits, and some cells may cause fireworks. As the cell failures would presumably be sequential, it's probably a better situation than a leaking gasoline tank.

Yes, the First Responders certainly do have some work to do to be prepared.

RE: High voltage equipment in battery-powerd cars

According to this, first responders should already have the necessary equipment and training for this type of fire:
https://resources.fireprotec.com/how-do-you-put-ou...

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

RE: High voltage equipment in battery-powerd cars

(OP)
Danke für die Antworten.

Aber das Problem liegt tiefer.

A)
Der BMW i3 hat eine 'Rettungstrennstelle'.
Im Fall eines Unfalls soll dort geschaltet werden.
Leider werden damit aber nicht die Kabel zwischen Batterie und Schalter spannungslos gemacht.
Diese Kabel kann niemand abschalten - sie stehen immer unter Spannung.

B)
Nach einem Unfall kann niemand von außen erkennen, welche Kabel noch unter Spannung stehen.
Man braucht einen Elektriker, der prüft, welche Teile keine Spannung mehr haben.

C)
Wenn ein Batterie Auto langsam in 3 Fuß tiefes Wasser fährt,
kann man mit dem BMW i3 (360 Volt) Elektrofischen.
Ein Retter braucht einen Gummianzug, wenn er zu dem Auto gehen will.

D) Eine Deutsche Feuerwehr braucht 15 bis 20 Minuten, um eine Unfallstelle zu erreichen.
In der Zeit müssen Ersthelfer arbeiten.
Kein Ersthelfer hat eine Ausbildung um an Elektro-Autos zu hantieren.

-------------------

Thanks for the answers.

But the problem is deeper.

A)
The BMW i3 has a 'rescue separation point'.
In case of an accident should be switched there.
Unfortunately, this does not mean that the cables between the battery and the switch are de-energized.
Nobody can switch off these cables - they are always live.

B)
After an accident, nobody can tell from the outside which cables are still live.
You need an electrician to check which parts are out of potential difference.

C)
When a battery car drives slowly into 3 feet of deep water,
you can with the BMW i3 (360 volt) electric fishing.
A rescuer needs a rubber suit if he want to go to the car.

D)
A German fire service takes 15 to 20 minutes to reach an accident site.
In the period first responders have to work.
No first responder has training to handle electric cars.


Max



RE: High voltage equipment in battery-powerd cars

(OP)
Die Differenzierung in Deutschland:

In der VDE 0140-1:2016-11 "Schutz gegen elektrischen Schlag - Gemeinsame Anforderungen für Anlagen und Betriebsmittel" befindet sich die Tabelle 1.

Diese legt fest:

Hochspannung: U >1000 V AC; U > 1500 V DC
Niederspannung: U ≤ 1000 V AC; U ≤ 1500 V DC
Kleinspannung: U ≤ 50 V AC; U ≤ 120 V DC

Nur der Bereich 'Kleinspannung' ist für den Mensch ungefährlich.

In den USA wird es ähnliche Grenzen geben.

-------------

The differentiation in Germany:

In VDE 0140-1: 2016-11 "Protection against electric shock - Common requirements for systems and equipment" is Table 1.

This states:

High voltage: U > 1000 V AC; U > 1500 V DC - IEC: Electrical arcing
Low voltage: U ≤ 1000 V AC; U ≤ 1500 V DC - IEC: Electrical shock
Extra low voltage: U ≤ 50 V AC; U ≤ 120 V DC - IEC: Low risk

Only the area 'Extra low voltage' is harmless for humans.

There will be similar limits in the US.


Max

RE: High voltage equipment in battery-powerd cars

Electric vehicles are already designed to prevent electric shocks in normal operation.

Service staff would need to be well trained and particularly cautious.

But what you're referring to is after an uncontrolled crash, where (in the worst case) everything is smashed open and damaged. Any safety standards would have to be precisely tailored to this situation, not general design standards. Such standards would presumably be spun off of automobile crash standards, and describe acceptable results.

Even then, they'd only be up to a certain speed. First Responders would still occasionally be faced with cases where the crash speed was beyond any standard. Hopefully in such cases the battery pack would then be sufficiently damaged that it no longer had a continuous series connection through 96 cells, with one end trailing on the ground, and the other end drapped across an unconscious passenger.

First Responders will need new training and some new equipment. The vehicle OEMs are already supporting this with their proactive information resources.

RE: High voltage equipment in battery-powerd cars

Except many fallen power lines might be the "Medium Voltage" from the top of the poles, and thus something like 2800 volts (?). Plus, they're almost guaranteed to be ground referenced.

For the e-cars: The OEMs are fairly proactive on all this.

RE: High voltage equipment in battery-powerd cars

While 2400-2800 Volts may be in use in some areas, I haven't encountered it for years now.
More common voltages that I have encountered start at about 7000 Volts to ground up to around 20,000 Volts to ground.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: High voltage equipment in battery-powerd cars

Cars give you both poles of a DC circuit. That's vastly different than an AC fault in which you have less than all three phases involved.

Car in the water - the only circuit is within the car itself. Drop one conductor of a 3-phase AC circuit into the water and you have vastly different conditions and considerations. The car and its DC is infinitely far more benign than if it were a single conductor of a 3-phase AC circuit.

RE: High voltage equipment in battery-powerd cars

Quote (CWR_Engineer)

A)
The BMW i3 has a 'rescue separation point'.
In case of an accident should be switched there.
Unfortunately, this does not mean that the cables between the battery and the switch are de-energized.
Nobody can switch off these cables - they are always live.

B)
After an accident, nobody can tell from the outside which cables are still live.
You need an electrician to check which parts are out of potential difference.

C)
When a battery car drives slowly into 3 feet of deep water,
you can with the BMW i3 (360 volt) electric fishing.
A rescuer needs a rubber suit if he want to go to the car.
I think it would be better if you spoke with an electrical engineer, not the first responders. Your concerns about the electrical aspect of the vehicle in the 3 situations above are of minimal concern to a responder. A DC-powered electric vehicle is vastly different than an AC-power transmission line, so the potential for a life-threatening shock you seem to be concerned with don't really exist.

Dan - Owner
http://www.Hi-TecDesigns.com

RE: High voltage equipment in battery-powerd cars

(OP)
Den Unterschied von DC Batterie Autos und AC Stromsystemen kenne ich.

Ich habe eine Lizenz als Verantwortliche Elektro Fachkraft AC/DC bis 20'000 Volt.

Das Problem ist das:

http://www.ktvu.com/news/tesla-crashes-catches-fir...

Brennende, verunfallte Batterie Autos

Daher meine Eingangsfrage:
Welche persönliche Schutzausrüstung haben US Feuerwehrmänner, um an DC - Elektroanlagen < 1'000 Volt zu hantieren ?

---------------------------------

I know the difference between DC battery cars and AC power systems.
I have a license as responsible electric specialist AC/DC up to 20'000 volts.

The problem is this:

http://www.ktvu.com/news/tesla-crashes-catches-fir...

Burning, accidental battery cars.

Hence my initial question:

Whitch protective equipment (DC < 1'000 Volt) of the fire-fighters do you have in the US ?

Max

RE: High voltage equipment in battery-powerd cars

(OP)
Ein Tesla hat ein Bordnetz mit 600 Volt.

Ist das Auto heile, besteht die Potentialdifferenz innerhalb des Autos zwischen den beiden Kabeln,
die aus der Batterie kommen.

Hat das Auto einen Unfall ist irgendwo im Auto die Potentialdifferenz von 600 Volt zwischen irgendwelchen Teilen.
(Undefinierter Zustand)

Hat das defekte Batterie Auto mit einem der beiden Kabel, die von der Batterie kommen,
einen Kontakt zu einem Metall Gegenstand der Straße (Lichtmast, Verkehrsschild, ...)
hat das Auto eine Potentialdifferenz von 600 Volt gegen Erde.

Welcher Mensch will dann ohne Schutzausrüstung am Unfallauto hantieren ?

Wer prüft den elektrischen Zustand des Autos nach einem Unfall ?

-----------

A Tesla has an electrical system with 600 volts.

If the car is intact, the potential difference inside the car is between the two cables,
which come from the battery.

Does the car have an accident somewhere in the car the potential difference of 600 volts between any parts.
(Undefined condition)

Has the broken battery car with one of the two cables coming from the battery,
a contact to a metal object of the street (light pole, road sign, ...)
the car has a potential difference of 600 volts to earth.

Which person wants to handle the accident car without protective equipment ?

Who checks the electric condition of the car after an accident ?


Max

RE: High voltage equipment in battery-powerd cars

(OP)
Danke.

Dieses Dokument kenne ich.
Es ist eine Hersteller-Seite zu Werbung.
Das echte Problem wird vernebelt.
Das grundsätzliche Problem hat weder BMW, noch Renault, noch Tesla erkannt.
Vielleicht sogar erkannt, aber nicht gelöst.
Elektrik kann man nicht hören, schmecken, sehen oder fühlen.

Dazu kommt das Problem der Lithium-Ionen-Akkus.
Lithium ist ein Alkali-Metall.
Metallbrände lassen sich mit üblichen Feuerlöschern nicht löschen.

Metallbrände sind der Brandklasse D zugeordnet.
Unter Metallbrand versteht man das unkontrollierte und Schaden verursachende Verbrennen von Metallen.
Bei den auftretenden hohen Temperaturen von über 2000 °C zersetzt sich Wasser in Wasserstoff und Sauerstoff.
Infolgedessen besteht die Gefahr von Knallgasexplosionen, weshalb Wasser als Löschmittel nicht verwendet werden darf.
Bei Brandtemperaturen von 1500 °C werden schon durch die Wärme rund 0,2 % des Wassers aufgespalten,
bis 2000 °C etwa 2 % und bei 2500 °C bereits 9 %. Das bedeutet, je heißer ein Metallbrand ist,
desto gefährlicher ist der Einsatz von Wasser.
CO2 ist ebenfalls ungeeignet, da Metalle bei hohen Temperaturen auch in CO2 brennen.
Dabei wird der Kohlenstoff unter Bildung von Metalloxiden reduziert.
Die Reaktion hält den Metallbrand aufrecht, ist aber nicht so heftig wie die mit Wasser.
Solche Brände werden durch Ersticken bekämpft. Steht Metallbrand-Löschpulver (D-Pulver) nicht zur Verfügung,
ist die Brandbekämpfung mit trockenem Sand, Zementpulver oder Natriumchlorid (Speise-, Streu- oder Viehsalz) effektiv,
die über dem Brandgut schmelzen und damit einen luftdichten Belag bilden, der das Feuer erstickt.
Metallbrand-Löschpulver besteht aus Salz mit Zusätzen.

ADR - Gefahrgutkennzeichnung:

Lithium Batterien in Ausrüstungen werden als Gefahrgut mit UN-3481 gekennzeichnet.
Diese Kennzeichnung ist nur beim Transport solcher Batterien erforderlich.

Ein Tesla S hat z.B. eine theoretische Batteriekapazität von 85'000 Wh.

Nach ADR 2009 ist es Gefahrgut, wenn Lithiumbatterien ab 100 Wh transportiert werden.

Nach ADR 2009 ist es kein Gefahrgut, wenn die Lithiumbatterien:
- beliebig groß sind,
- in einem Fahrzeug eingebaut sind
- zu dessen Antrieb dienen.

Somit werden die Augen vor dem tatsächlichen Gefahrenpotential verschlossen.

--------------------------------

Thank you.

I know this document.
It is a manufacturer page for advertising.
The real problem is fogged.
The fundamental problem has not recognized BMW, nor Renault, nor Tesla.
Maybe even recognized, but not solved.
Electricity can not be heard, tasted, seen or felt.

There is also the problem of lithium-ion batteries.
Lithium is an alkali metal.
Metal fires can not be extinguished with conventional fire extinguishers.

Metal fires are assigned to (german) fire class D.
Metal burning is the uncontrolled and harmful burning of metals.
At the occurring high temperatures of over 2000 ° C water decomposes into hydrogen and oxygen.
As a result, there is a danger of explosive gas explosions, which is why water must not be used as extinguishing agent.
At fire temperatures of 1500 ° C, around 0.2% of the water is already split by the heat,
up to 2000 ° C about 2% and at 2500 ° C already 9%. That means, the hotter a metal fire is,
the more dangerous is the use of water.
CO2 is also unsuitable because metals also burn in CO2 at high temperatures.
The carbon is reduced to form metal oxides.
The reaction keeps the metal fire upright, but it is not as heavy as it is with water.
Such fires are combatted by suffocation. If metal fire extinguishing powder (D-powder) is not available,
If fire-fighting with dry sand, cement powder or sodium chloride (food, litter or cattle salt) is effective,
which melt over the fire and thus form an airtight coating that stifles the fire.
Metal fire extinguisher powder consists of salt with additives.

ADR - Dangerous Goods Identification:

Lithium batteries in equipment are labeled as Dangerous Goods with UN-3481.
This marking is required only when transporting such batteries.

A Tesla S has e.g. a theoretical battery capacity of 85'000 Wh.

According to ADR 2009, it is dangerous goods when lithium batteries are transported from 100 Wh.

According to ADR 2009, it is not a dangerous good if the lithium batteries:
- are any size
- are installed in a vehicle
- serve for its drive.

Thus, the eyes are closed from the actual danger potential.

Max





RE: High voltage equipment in battery-powerd cars

Quote (CWR_Engineer)

I know the difference between DC battery cars and AC power systems.
I have a license as responsible electric specialist AC/DC up to 20'000 volts.

The problem is this:

http://www.ktvu.com/news/tesla-crashes-catches-fir...

Burning, accidental battery cars.

Hence my initial question:

Whitch protective equipment (DC < 1'000 Volt) of the fire-fighters do you have in the US ?
If you understand the difference between DC and AC, why are you worried about people standing in the water near an electric vehicle? This statement alone tells me you don't understand. An energized car sitting in a body of water will VERY quickly find itself de-energized (and likely catch fire)... but there's no danger form an electric shock point of view.

You've brought up the issue of electricity being a problem, yet you keep tying it back to the resultant fire... gasoline-powered vehicles catch fire all of the time. So which are you truly concerned about... electricity, or fire? Because the electricity part of the question is (mostly) irrelevant.

Quote (CWR_Engineer)

At the occurring high temperatures of over 2000 ° C water decomposes into hydrogen and oxygen.
As a result, there is a danger of explosive gas explosions, which is why water must not be used as extinguishing agent.
If we were discussing a chemical plant where tens of thousands of gallons of water per minute were being dumped on a large metal fire in an enclosed warehouse, I might agree... but we're talking about a Tesla on the open road. It is hard to imagine a cloud of hydrogen and/or oxygen building to a large enough concentration to cause any more damage than a fire that's already burning at 2000°C.

I feel you are worrying about imagined issues that aren't really a problem in the real world... but I could be wrong.

Dan - Owner
http://www.Hi-TecDesigns.com

RE: High voltage equipment in battery-powerd cars

It's not really the distinction between AC and DC as such. It's that grid AC is universally ground referenced, where as a DC battery pack in a car isn't.

In an accident, to have a shock hazard, one end of the pack would have to touch the ground while the other end is connected to the chassis. All while maintaining the chassis isolation from ground. And having none of the safety systems working. It's getting on towards pretty unlikely.

For those worried about shocks, buy some approved rubber gloves and a suitable meter. And participate in the appropriate training.

RE: High voltage equipment in battery-powerd cars

>Whitch protective equipment (DC < 1'000 Volt) of the fire-fighters do you have ?

I don't know, I'm not a first responder. But the neighbor is a fire fighter so I'll ask him.

But when the NFPA's Alternative Fuel Vehicles Safety Traing Program Emergency Field Guide, 2015 Edition, (Now Includes Hybrid, Electric, Fuel Cell, and Gaseous Fuel Vehicles) was published it said:



That guide is now 3 years old, so the situation might have changed, but like most things, it would be a local case department by department basis in the US.

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