8bits
Posts: 13
Joined: Sat May 04, 2013 4:37 am

Re: BareEVSE - an EVSE circuit for under $5

Sat May 04, 2013 9:07 am

EVDRIVER wrote:I would consider making an open EVSE or buy something that is made properly. Since you are not in the USA you don't have to worry about the liability and code violations this presents but it lacks basic common sense design and safety. I know products are expensive there but you may have better options. Also, reliability is something to consider as well.
"buy something that is made properly" ---> can you please suggest me? as I told, the original from my car doesn't work and so I will need to "disable" some safety, probably the earth resistance measure.

I have experience to program firmware (for ARM mainly) and I can make my own small prototype boards -- I will do for sure my EVSE using OpenEVSE and BareEVSE information!!! :-) -- I am thankfull to both projects!

QueenBee
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Leaf Number: 2062
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Re: BareEVSE - an EVSE circuit for under $5

Sat May 04, 2013 11:15 am

8bits wrote:as I told, the original from my car doesn't work and so I will need to "disable" some safety, probably the earth resistance measure
Did your electrician have any ideas on why your garages electrical system is different than normal and thus why the EVSE enters a fault state?

8bits
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Re: BareEVSE - an EVSE circuit for under $5

Sat May 04, 2013 11:30 am

QueenBee wrote:
8bits wrote:as I told, the original from my car doesn't work and so I will need to "disable" some safety, probably the earth resistance measure
Did your electrician have any ideas on why your garages electrical system is different than normal and thus why the EVSE enters a fault state?
Earth resistance value may be a bit out of the max specification.

QueenBee
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Re: BareEVSE - an EVSE circuit for under $5

Sat May 04, 2013 1:24 pm

8bits wrote:
QueenBee wrote:
8bits wrote:as I told, the original from my car doesn't work and so I will need to "disable" some safety, probably the earth resistance measure
Did your electrician have any ideas on why your garages electrical system is different than normal and thus why the EVSE enters a fault state?
Earth resistance value may be a bit out of the max specification.
I think an easier approach might be outlined here: http://www.mynissanleaf.com/viewtopic.p ... 27#p205127" onclick="window.open(this.href);return false;

Please note that I do not have the proper knowledge nor information about your situation to determine if this is a safe solution for you so please ensure that you've consulted someone familiar with your situation and who has the experience to properly determine the safety.

8bits
Posts: 13
Joined: Sat May 04, 2013 4:37 am

Re: BareEVSE - an EVSE circuit for under $5

Sat May 04, 2013 2:01 pm

QueenBee wrote: I think an easier approach might be outlined here: http://www.mynissanleaf.com/viewtopic.p ... 27#p205127" onclick="window.open(this.href);return false;

Please note that I do not have the proper knowledge nor information about your situation to determine if this is a safe solution for you so please ensure that you've consulted someone familiar with your situation and who has the experience to properly determine the safety.
THANKS!! I will explore this option.

8bits
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Joined: Sat May 04, 2013 4:37 am

Re: BareEVSE - an EVSE circuit for under $5

Mon May 13, 2013 7:42 am

My EVSE, of my Smart electric car still doesn't work. I designed the NE555 circuit so I can visualize how I will prototype it. I also used LTSpice to simulate and it seems to have the output I am looking for - ~5us --> ~8A current charge.

Image

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davewill
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Re: BareEVSE - an EVSE circuit for under $5

Mon May 13, 2013 10:15 am

8bits wrote:My EVSE, of my Smart electric car still doesn't work. I designed the NE555 circuit so I can visualize how I will prototype it. I also used LTSpice to simulate and it seems to have the output I am looking for - ~5us --> ~8A current charge.
Your Smart EV is probably smart enough not to work with this circuit. The LEAF really shouldn't. This design cuts many, many corners and I would expect if to fail with a lot of EVs.
2014 Rav4 EV, Blizzard Pearl White
2011 LEAF SL w/QC, Blue Ocean, returned at end of lease

chris1howell
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Leaf Number: 4122
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Re: BareEVSE - an EVSE circuit for under $5

Mon May 13, 2013 12:32 pm

8bits wrote:Also latest OpenEVSE is BIG, uses an LCD that I would not use most of the time - I am looking for someting very small (just as you did) and that works with the same current - maybe no more than some little switchs to choose from 4 different current values.
This marks the first time I have been told the current OpenEVSE board is BIG (and in all caps)... at 2.2"x 1.75"x 3/4" it includes an integrated Power Supply most comment on how tiny it is. I do not think much can be done to make it smaller while maintaining all the important J1772 safety features (GFCI, Ground check, Stuck Relay detection, etc.)

The LCD is also optional, it works great without a display.
2011 LEAF: Red SL #04122
2012 Tesla Model S #01530
EVSE: OpenEVSE, 40A L1/L2 -- http://www.openevse.com
PV System: 28 x 210W -> 5.8 kW DC

OpenEVSE Store: http://store.openevse.com

8bits
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Re: BareEVSE - an EVSE circuit for under $5

Mon May 13, 2013 2:16 pm

davewill wrote:Your Smart EV is probably smart enough not to work with this circuit. The LEAF really shouldn't. This design cuts many, many corners and I would expect if to fail with a lot of EVs.
What do you think is the minimum for an EVSE work on a car like mine?

I must say I prototyped that small and simple circuit and I couldn't get any wave out of it :-( :-( --- maybe I will go with a microcontroller...

8bits
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Joined: Sat May 04, 2013 4:37 am

Re: BareEVSE - an EVSE circuit for under $5

Mon May 13, 2013 2:26 pm

chris1howell wrote:
8bits wrote:Also latest OpenEVSE is BIG, uses an LCD that I would not use most of the time - I am looking for someting very small (just as you did) and that works with the same current - maybe no more than some little switchs to choose from 4 different current values.
This marks the first time I have been told the current OpenEVSE board is BIG (and in all caps)... at 2.2"x 1.75"x 3/4" it includes an integrated Power Supply most comment on how tiny it is. I do not think much can be done to make it smaller while maintaining all the important J1772 safety features (GFCI, Ground check, Stuck Relay detection, etc.)

The LCD is also optional, it works great without a display.
Hello chris1howell!!

Thank you for all of your work in OpenSource! - your work inspires me, thanks.

I would like to get an "EVSE" small enough and cheap, to fit into a J1772 plug, just like BareEVSE. Also I am not looking for the safety features - thanks to them, the original EVSE that came with my car doesn't work. My electric circuit is ok and have protections.

I wish I could buy OpenEVSE assembled and tested, and get it at my home in 5 days.

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