Battery disconnect

[Mark Brems]

Hey All,

I am planning to put an emergency disconnect between the battery pack and the main contactor, so I can interrupt the pack voltage to perform service on any of the EV components. I'm running 36 cells for a total of 115 volts, and all I need is a single pole switch. I don't plan on operating the switch hot, while the contactor is closed, although I am toying with the idea of hardwiring the DC/DC directly to the pack.

Does anybody have suggestions for a good disconnect?  The most promising looks to be the Albright ED250, although it's rated for 96 volts, and 250 amps continuous. I'm just not sure that is enough.

To confuse matters, it is offered at two wildly differing prices:

$40.00 - http://www.cloudelectric.com/product-p/sw-ed250b.htm
$135.00 - http://www.evparts.com/products/street-vehicle/switches--dot/battery-disconnects---street-vehicle/sw2514.htm

Thoughts?

Thanks,
McB

[Richard Rodriguez]

Hi Mark,  I use the Albright Disconnect switch. shown here.  I have 38 cells @121.4V.

I was getting a weird buzzing sound from the switch a while back but it turns out it was a loose connection at a different location in my pack at a battery terminal that (I think) was causing the Buzz.

Since I fixed the loose connection no problems.  WOW $40 bucks seems like a great deal.

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[Peter Thompson]

Hi Mark,

I use an Anderson 350 connector with a mechanism to pry the connector
apart.
Connector:
http://www.cloudelectric.com/product-p/ds-124208.htm

Mechanism:
http://www.evparts.com/products/street-vehicle/connectors--dot/manual-disconnects---street-vehicle/cn9551.htm

The one from EVParts is slightly different from mine, but mine is
also several years old. :) The nice thing about mine is that I can
tell at a glance that the pack is disconnected - if the connectors are
separated, then the pack is too. ;)

Cheers,
Peter

On May 7, 7:59 pm, Richard Rodriguez <rickro...@san.rr.com> wrote:
> Hi Mark,  I use the Albright Disconnect switch. shown here.  I have 38 cells @121.4V.
> I was getting a weird buzzing sound from the switch a while back but it turns out it was a loose connection at a different location in my pack at a battery terminal that (I think) was causing the Buzz.
> Since I fixed the loose connection no problems.  WOW $40 bucks seems like a great deal.
>
> On May 7, 2012, at 6:49 PM, Mark Brems wrote:
>
>
>
>
>
>
>
> > Hey All,
>
> > I am planning to put an emergency disconnect between the battery pack and the main contactor, so I can interrupt the pack voltage to perform service on any of the EV components. I'm running 36 cells for a total of 115 volts, and all I need is a single pole switch. I don't plan on operating the switch hot, while the contactor is closed, although I am toying with the idea of hardwiring the DC/DC directly to the pack.
>
> > Does anybody have suggestions for a good disconnect?  The most promising looks to be the Albright ED250, although it's rated for 96 volts, and 250 amps continuous. I'm just not sure that is enough.
>
> > To confuse matters, it is offered at two wildly differing prices:
>
> > $40.00 -http://www.cloudelectric.com/product-p/sw-ed250b.htm

> > $135.00 -http://www.evparts.com/products/street-vehicle/switches--dot/battery-...

[Mark Brems]

I can only imagine the Anderson connector takes up a lot of real estate
if it accepts 2/0 gauge welding cable.

[Peter Thompson]

It does use a bit of space, but I wasn't worried about it too much -
rather have a safely disconnected pack than a nasty shock. Having
shocked myself with about 50v, 370v is not at all inviting.

You can see a picture of the rear trunk on my blog:
http://cruzware.com/peter/blog/

Cheers, Peter

On May 8, 9:20 am, Mark Brems <mcbr...@gmail.com> wrote:
> I can only imagine the Anderson connector takes up a lot of real estate
> if it accepts 2/0 gauge welding cable.
>

> On Tue, May 8, 2012 at 8:05 AM, Peter Thompson <pthompson...@gmail.com>wrote:
>
>
>
>
>
>
>
> > Hi Mark,
>
> > I use an Anderson 350 connector with a mechanism to pry the connector
> > apart.
> > Connector:
> >http://www.cloudelectric.com/product-p/ds-124208.htm
>
> > Mechanism:
>

> >http://www.evparts.com/products/street-vehicle/connectors--dot/manual...

[Mark Brems]

Well, I ended up buying the Albright ED250B, with magnetic blowouts:

http://www.cloudelectric.com/product-p/sw-ed250b.htm

It's a great buy - Don't know what Cloud Electric has up their sleeve.
The switch is very beefy, and will easily accept 1/0 or 2/0 cable with
5/16" lugs. It also snaps quite well when operated. The switch is ON
when pulled out, and disconnected when pushed.

I was planning to mount in my center console, at the bottom, just in
front of the shifter boot. It will be breaking the cable that joins the front
and rear packs as it travels up the tunnel. It won't require a large hole
in the console panel to mount.

So far so good. I was pleased that the switch was hefty, but didn't expect
the button to be so large. It's like a sizable clown nose - 3 to 4 inches
in diameter. It screws onto the switch shaft with an 8mm thread (Albright
is British).

I hope you've been entertained thus far. The question is whether anybody
knows of a source for 8mm thread clown noses that are maybe half
this size. Maybe something that will look more James Bond-ish on my
console.

Cheers,
McB

[Peter Thompson]

Hah - James Bond-ish. I'll have to remember that one. :)

Try McMaster-Carr - they have EVERYTHING. It's not the easiest site
to search tho.
http://www.mcmaster.com

Cheers, Peter

[Ben A]

I'm a little late joining the thread, but....

I found a big honkin' surplus/remanufactured Square-D breaker for mine.  250VDC/1250A (10,000AIC).  The cute part was I used wire rope to tie it to the heater control just behind the shifter (the lever with the big red handle -- perfect for a safety disconnect).

My main concern was the possibility that my controller could fail ON -- I needed a way to kill the motor without using the clutch and letting the commutator fly to pieces.  I have a 178V pack, so I couldn't get away with the much more readily available 160V breakers, such as this one:  http://www.kta-ev.com/Airpax_Circuit_Breaker_250_400A_160V_p/jle-1-1-53-3-b4-250.htm

So far, I've only had to use it to ensure safety while servicing the car.

-Ben

[914Mike]

Here's my solution:

http://www.evolveelectrics.com/Contactors.html

750V and 400A ratings. Combined with a red 40mm mushroom (or "clown nose") switch:

http://www.digikey.com/product-search/en?x=0&y=0&lang=en&site=us&KeyWords=87941-08