I ask again.  Is it a relay or a contactor?  And before you answer, remember 
that a relay is tested to a different set of requirements than a contactor.

The problem with a solid state relay is not the failure mode but the fact that 
a solid state device always has some level of leakage current.  In other words, 
a SSD cannot provide complete isolation from a source.  Have you every seen a 
UL listed (UL489) solid state branch circuit protection device?


________________________________
From: EV <ev-boun...@lists.evdl.org> on behalf of Cor van de Water via EV 
<ev@lists.evdl.org>
Sent: Tuesday, July 11, 2017 4:50 PM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] ? Is this really a Smart Fortwo ED EV that burnt to acrisp ?

Robert,

full galvanic isolation requires a mechanical relay in the EVSE,

as the failure mode of a "solid state relay" (fancy words for
essentially a transistor) is to fail "ON" (shorted).

That is not an acceptable failure mode when the point of the EVSE is to
disconnect power in failure situations.

Cor.



From: ROBERT [mailto:bhensle...@msn.com]
Sent: Tuesday, July 11, 2017 4:09 PM
To: Cor van de Water; Electric Vehicle Discussion List
Subject: Re: [EVDL] ? Is this really a Smart Fortwo ED EV that burnt to
acrisp ?



Cor van de Water wrote: " Remember that an EVSE has a relay interrupting
the 240V supply."
  Is this relay a mechanical relay or a contactor or solid state relay?




________________________________

From: EV <ev-boun...@lists.evdl.org> on behalf of Cor van de Water via
EV <ev@lists.evdl.org>
Sent: Tuesday, July 11, 2017 4:01 PM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] ? Is this really a Smart Fortwo ED EV that burnt to
acrisp ?



I looked at the pictures and wondered the same - if the yellow cord was
the connection
between car and EVSE then the only way the EVSE coud set the car on fire
would be burning bits to fall off and somehow reach the car, as most of
the cord appears undamaged.
However, it appears that the coiled yellow cord was enclosed in a
sleeve, the tube-like thingy
that is laying on the ground. So, it is possible that a fire in the EVSE
traveled over the *outside* of
the sleeve and set the last few feet of charging cord on fire, which
then lit the car up.
The weird thing is that the least affected spot on the whole vehicle is
directy under the
charging plug, as that tire appears complete while all other rims have
burned off their tires,
in the front therims are molten as well, so the temps must have been
around 1000 deg C inside the fire.
That is still possible, even if the car was lit up in the back via the
cord, it only takes a light breeze from the back
to cool the back side of an object and drive the flames in the forward
direction...

-----Original Message-----
From: EV [mailto:ev-boun...@lists.evdl.org] On Behalf Of Roger Stockton
via EV
Sent: Tuesday, July 11, 2017 3:41 PM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] ? Is this really a Smart Fortwo ED EV that burnt to
acrisp ?

Cor van de Water wrote:

> Remember that an EVSE has a relay interrupting the 240V supply.
> As I related before, any wire that is damaged or improperly tightened
> can burn, even if not overloaded for the spec of the wire.
> If the EVSE is not frequently used, there is the risk of corrosion of
> the relay contacts, adding to the resistance and easily causing
> overheating of the relay or even starting a fire.

Even if this were the case, it would result in the EVSE itself perhaps
catching fire, or otherwise failing and interrupting AC power to the
car's on-board charger.

It is difficult to imagine a scenario where the wall-mounted EVSE
visible in the pictures could burn with such intensity as to catch a
nearby vehicle on fire in this way.

I find it especially difficult to believe given that some of the photos
clearly show the charge cord still attached to the vehicle, and aside
for the few feet immediately at the car end of the cord, the cord itself
appears undamaged.

Cheers,

Roger.

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